Guardian Rank intentionally resets every season, with Edge of Fate they brought players down further (rank 2) as they reworked it. As for Prismatic, you do have the subclass unlocked (as you've done the mission to unlock it) - API says you own The Final Shape on PSN but not Steam, so if you're trying to access the subclass on Steam you will need to purchase TFS there. If you do own TFS on Steam then you should try verifying game files and then contact Steam support for them to look into it further. Expansions are licensed by the platforms and almost all support in regards to licenses will need to go through them.