Failed to verify username

So i was going to join my minecraft java edition server then suddenly i having the same issue like MC-256286 i read the comments, ok it was a username issue, my new account is registered i play mcje 1.20.4 then suddenly when i join the server there was the error, i quickly see the server logs the there was a another error 'Username 'Scratch2033YT' tried to join with an invalid session' Scratch2033YT is my username, please fix this, the client i use is UltimMC.
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