The types ‘Season Athlete Document’ and ‘Seasonal Team Document’ are related to a specific season (e.g. to the team of season 2020/2021).
If you want to link documents to a team without the seasonal filter on it, then choose ‘Team Document’ or ‘Person document’.
General info: user functionalities depend on the roles & permissions settings. If a certain functionality does not work within your user account, this will be because you don't have sufficient permissions for this.