@Miri123zoro There was a similar post about this a while back.
You cannot change your date of birth in-game, the only solution is to save your progress and then uninstall the game.
Once that is done, reinstall it, you should then be prompted to enter your correct date of birth.
I dunno why people can't do this the first time, maybe it's the silly way they ask you to do it - I had to scroll way back through every year and month for decades until I finally got to the right year 🤣
Anyway, after that, do the tutorial until you see the settings icon on your screen (crossed spanner and screwdriver, top right side)
Tap it and log in to either Google Play or whatever you use to get your apps or Facebook.
Hopefully you'll be back where you left off by then :-)