I’m using Android 8 and using the same app version 2.5.36. I am not seeing this zoom issue on any of my devices. Have you tried any troubleshooting steps yet like uninstalling/reinstalling the app or anything?
Just to confirm, you are referring to the 12 sec cloud event videos and not the playback from microSD card, correct?
Edit: You might want to check your phone’s resolution settings. This happened once before with another user having this issue.
Same issue in this thread below: