PTA permissions are directly linked to the term of your office. Therefore, once your office term expires so do your PTA permissions. At first it may see that you still have current rights in the system but these may only reflect administrative permissions which are not PTA permissions.
To resolve this issue contact a current officer with permissions in the system to extend your permission set, or request permissions by going to www.justbetweenfriends.com/ptaquickstart and entering you National PTA ID number, then following the prompts, or by clicking on the contact us link for Just Between Friends.