When adding a game or practice through the Persona view > Calendar, teams do not show up to be selected in the drop-down.
When adding a game/practice through the calendar, the current date is used to determine the current Athletic season so the system knows which teams are active and should be available in the list. If the current date is in between seasons, no teams will show in the drop-down.
To adjust Athletic Season dates to ensure there are no gaps:
Go to Core > School > Years & Terms
Select the appropriate School Year and School Level
Edit the Begin Date or End Date for Athletics Seasons to ensure there are no gaps between seasons