playing on 1.21.1 on a modpack

at first when i imported over the old files from the 1.20.4 version of the modpack, the entire configuration disappeared and everything was back to default (Menu Item #1 , #2 etc etc) so i just manually added them back in

was working for a while but when i exited the game and came back everything disappeared again

the json file is in its config folder though so idk why it keeps going poof

Could you please provide your menu.json file?

I'm not able to reproduce myself, so would have to have the same setup as you to hopefully find a solution :)