If you tap on a match from the list of matches in the app and you don't see the Enter Score button on the Match Overview page, then it might be because of the following reasons:
Scores are locked
1. The scores have been locked because they have been entered already and the score has been manually approved and auto-locked, or auto-approved and locked depending on the settings in:
Setup > Settings > Approval and Locking (tab)
2. Default settings for security access to enter scores have been overridden.
A League Administrator needs to check the security access settings for Team Administrators.
Setup > Settings > Roles (tab)
Then click edit next to the Team Administrator role and check that they can enter scores and statistics.