The GYM - stopped gaining XP

I was leveling up my fighter (Jonathan Martinez) in the Gym to get him to level 99 for the PS trophy "Loyalist". I was putting him on training every day multiple times, also I was fighting with him online to gain bonus XP and yesterday as on 17.07.2026 it just showed 0 / 0 XP on level 59 and I stopped gaining XP on him. Its not gaining XP from traning and neither from fighting. Please fix this or help me with this issue, because I put so much time into it and I dont want to repeat it all over again. Thank you!