Canada-US-INTL trips can only check-in on UA.com but not in App
Few months ago, I noticed I can no longer check-in in UA app, the normal check-in failed message was given, while I am able to check-in on UA.com without any problem. This become normal for all my INTL trips, no matter Canada-US-INTL or INTL-US-Canada, I just checked-in my tomorrow's FRA-IAD-YYZ flight and no surprise same situation.
Does anyone else has same issue? Any way to fix it? It's not a big issue however in most cases App check-in is more fast and less time consuming.
Thanks all!