I was testing another app and found that there is a subtle change that has taken place lately. The starts and opens event are treated differently now if the app started from a computer or from a mobile.
I was modifying this app for another member of the community and found that if I have the codes under screen open it works from the computer but does not work from the mobile.
Could this be the issue that you are facing?
Do you have some codes in the screen opens block that needs to run for a successful login?