Ahhhh alrighty, that is indeed a bit of an issue.
That error would indicate the offer and answer aren’t matching due to using different fingerprints.
The answer has to correspond to some degree with the received offer.
It appears as if you are creating multiple offers and answers and of-course that mixed with sending them over to the other device which is doing the same will end up with potential mismatches.
Over here recently i explained the sequence to get a call connected correctly.
Try logging all of the events as they are happening and compare the sequence.