There is a known issue with older revisions of the 880LM wall button. See this thread: Issue thread (GDO blaq): Chamberlain HD930EV / Round Yellow Button
The solution is to replace the 880LM with one that was manufactured after 2017. There should be a date code printed on the back of the 880LM, and I suspect yours is one of the older ones from 2014~2016 that for whatever reason are incompatible.