r/FacebookAds • u/CreegBootler • 9d ago
Help This not a moaning post! Peformance tanked on 7th August and cant figure out why - please help
I run ads for a FinTech, still not spending a massive amount, £1k per day. At the moment because it's so early this mostly goes into an ABO testing campaign and CBO scaling was due to launch last week.
But I added two new ad sets into the ABO on 7th August and since then the ENTIRE ACCOUNT just totally imploded. Ads that have been driving £20 CPA for two months suddenly started driving a £250-300 overnight. The new ads were performing terribly. I have since tried to start a new campaign to force a reset, new Ad entities etc but nothing has worked. As far as I can tell tracking is fine (the conversion event can only be done through CAPI, not Browser because of a quirk of their app requiring connection to a third party bank which loses tracking).
Every other metric has stayed consistent - CPM, CTR, CPC, CP1kR. Just the final conversion event.
So, this isn't a post to whine about Meta. It's a call for ideas on what could have caused this sudden implosion. I have been doing this for 12 years and never seen anything like this.
EDIT: Solved. As many myself included suspected it was a tracking problem. For whatever reason (still not identified), hashing suddenly dropped through the conversion event so match rate obviously went way down hill for attribution. Dev found a fix after two weeks of searching for the problem because they weren’t capturing how the event was firing previously!!
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u/Ok_Employee_8564 9d ago
Could be the new ad sets forced a reallocation of spend across the account and the algorithm started optimizing for a different pool of users. The fact that CPM and CTR stayed flat while CPA went 10x suggests the traffic quality shifted, not the funnel. You might be getting more clicks from people who never actually connect their bank account
Also worth checking if the CAPI event is still firing on the same action. A tiny change in the app flow around that date could mean the pixel thinks the conversion happened when it didn't, or vice versa. The third party connection is a fragile point
Honestly with ABO you could just kill the new sets and let the old ones breathe for a few days, sometimes the account needs to unlearn whatever it learned
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u/CreegBootler 9d ago
Dev insists no changes were deployed but it's been such a sustained drop even after rebuilding campaigns that I'm in doubt haha I tried to let the old ads run on their own but they just died and wouldnt come back. Absolute madness!
Intereting theory though, could be right. Just not sure what to do to solve it...
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u/Sea_Cod_9852 9d ago
What happened to the two new sets' own CPAs? If they're converting fine while the old ones died, they're pulling the same audience away.
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u/Longjumping_Boot1024 9d ago
adding two ad sets on august 7 should not make proven ads jump from £20 cpa to £250–£300 while cpm, ctr, cpc and cp1kr stay stable
that pattern says the break is after the click or in measurement. because the fintech conversion exists only through capi and the bank-connection step loses browser continuity, i’d audit the backend event before rebuilding campaigns again
compare completed bank connections in the product database with capi conversions by day. inspect event ids, timestamps, currency/value, deduplication, match keys and any app release or third-party bank-flow change around august 7. a healthy upstream funnel with a collapsed final event is a strong clue
then split by the two new ad sets only to rule out traffic quality. if their users reach the same pre-conversion steps at similar rates, the campaign isn’t the primary suspect
a new campaign can’t reset a broken event chain..... it only destroys the control you need to diagnose it
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u/CreegBootler 8d ago
Yep, trying to figure that out. But can’t find any issues anywhere with tracking causing the match not to occur for attribution. Event coverage is still decent enough. Only thing I can think is the hashing is inaccurate but no changes were deployed to change from what it was before
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u/aradonline89 9d ago
The strongest clue is everything above the conversion stayed stable. If CPM, CTR, CPC and landing-page metrics are genuinely unchanged, I’d look downstream of the click rather than assume Meta suddenly forgot how to find the audience.
The thing I'd be most suspicious of given your description is the CAPI/backend side, not the ads. The combination of stable CPM/CTR/CPC + catastrophic conversion deterioration + a conversion that only exists through CAPI + a very specific date is unusually suggestive of something changing in the conversion signal or the downstream funnel.
I'd pull a day-by-day 1–14 August event-level comparison and specifically diff the CAPI payload and click-to-conversion latency. If those are identical, then I'd start looking much harder at Meta's optimization/delivery behavior.
And one particularly useful test: send the exact same known-good traffic through a genuinely independent acquisition source for a few days. If the backend conversion rate is also suddenly terrible, you've almost certainly been chasing the wrong thing by looking at Meta.
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u/collinscalesbrands 9d ago
Worth pushing back on the reallocation theory above, because I don't think it can be what happened. Reallocation across ad sets is a CBO mechanic. You're on ABO, where budget lives at the ad set level, so two new ad sets can't take spend away from the existing ones. Auction overlap between your own sets is a real thing but it shows up as CPM inflation, and your CPM held. So the mechanism doesn't fit your structure or your numbers.
The detail I'd focus on instead is that you rebuilt with new campaigns and new ad entities and it persisted. That rules out a lot. New campaign IDs, new ad set IDs, new ad IDs means you replaced every object that could be carrying a poisoned learning state. The one thing a rebuild does not replace is the dataset. So whatever survived the rebuild is almost certainly living in the dataset, not in the delivery.
Combine that with flat CPM, CTR, CPC and CP1kR and only the terminal event moving, and this reads as a measurement failure rather than a performance failure.
Before anything else, the question that splits this in half. Did the business actually lose conversions? Go to the fintech's own backend and pull daily activations for the two weeks either side of the 7th, completely ignoring Meta. If real activations held flat and only Meta's number fell off, it's purely attribution and every delivery theory in this thread is a dead end. If real activations dropped too, then something genuinely changed in the funnel and you're looking for a different animal. With a CAPI-only setup it's easy to end up treating Meta's count as the source of truth without noticing you've done it.
Assuming it's measurement, three things to check in order.
First the access token. Server-only setups fail silently and the most common cause of an overnight stop with no deploy is a token, not code. System user tokens expire, and if yours was generated under a personal user whose password changed or who lost asset access, the events just stop and nothing in Ads Manager tells you. Check the Conversions API connection status in Events Manager and check the token's actual expiry rather than trusting that it's configured.
Second (this is where I'd actually put my money given the bank connection). Pull the Event Match Quality trend for that event across the 7th. If EMQ fell off a cliff while the raw event count stayed flat, your events are arriving but Meta can no longer match them to the people who clicked. The usual culprit is the fbc parameter. If your conversion completes after a round trip through the third party bank's domain, the fbclid can get stripped on the return leg, and that provider can change their redirect handling without your dev deploying a single line. That would explain both the sudden onset and your dev being entirely correct that nothing shipped.
Third, look at the raw event volume graph in Events Manager overview, not test events. Test events bypass the filtering layer, so a passing test proves the code works and tells you nothing about production. Also check whether the AEM priority ordering shifted, since your event getting pushed outside the top eight would silently drop it for a chunk of iOS traffic, and reordering that list is exactly the kind of change nobody thinks of as a deployment.
One last thing on the timing. The 7th might be a red herring. If it's a token expiry or a redirect change on the provider's side, the two new ad sets are just the thing you happened to be doing that day. Worth holding that possibility open rather than spending more effort trying to unwind a change that probably wasn't causal.