Ran across this and thought it worth posting in case it can help anyone. The guy did a pretty exhaustive look at what’s going on / needs to go on when this device learns codes. He includes some pretty specific suggestions to improve your code capturing that are surprisingly necessary according to him.
May need Reddit to see this, didn’t use to.
He included a link to a Transcoder to test captured codes for format conformity to NEC standards and other derived information.
Edit Add:
Another useful resource for IR Codes
Aside: There’s a handful of useful threads on this device which would have been a reasonable repository for ongoing comment. Granted some are a couple years old, but maybe this one or another can stay open so folks can discuss what they’re discovering with this affordable Zigbee IR Remote alternative.