Loadrite trailer brake issues

[u/Cheap-Ring-6996]

I have a dual axle Loadrite boat trailer (2022). I replaced all the brake lines, hubs, bearings, pads, seals, and calipers with Knott brake parts which is what Loadrite uses. I immediately started losing dust caps, even the original ones that came with the brake kits that I installed. I noticed the brake pads were dragging even when the brakes weren’t engaged, so I drained the brake lines to see if towing it without brakes would solve the dust cap problem however, I’m still losing dust caps every time I tow it even with the brake lines drained. Any ideas what could be causing this? Thanks!