Packaging Error

Hello, please can anyone help me with this error?
I upgraded fomr 4.19 to 4.22 and when I try to package the game, this error pops up
LogPackageName: Error: DoesPackageExist: DoesPackageExist FAILED: ‘(/Game/GenericShooter/BlueprintLogic/GameModes/BP_Deathmatch’ is not a standard unreal filename or a long path name. Reason: Path should start with a ‘/’

I haven’t changed anything and 4.19 packaged normally. I searched for the reference but couldn’t find it. I don’t get any message in log about which blueprint has this refference. I looked into every class that has got the gamemode refferenced but I haven’t found anything. My project is full blueprints but i am using source version so It has some source code generated.