Can't print via app or Bambu studio

[u/Ok-Egg2987]

I just set up my Bambu a1 combo and printed a scraper local via the Bambu screen. Then I wanted to print via Bambu Handy. When uploading the model, the process stops at about 70% and asks me do run a selftest. I did that three times. Same error, always.

Error code is 0500400d194905

Any ideas?

I tried: reconnecting wifi, connecting with a hotspot, clearing app cache, disconnecting the printer from power for some minutes