Hello poo poo,
Since the recovery form says that Gmail address is not recognized, I would first confirm which Microsoft account actually owns the Minecraft purchase rather than submitting the recovery form again.
Please try Microsoft’s Sign-in Helper with the Gmail address you used: Microsoft Sign-in Helper
Also, on the PC where you purchased or played Minecraft, check whether the Microsoft Store, Xbox app, or Minecraft Launcher is still signed in. If so, please check which Microsoft account/email is shown there.
Once you identify the Microsoft account username associated with the purchase, you can use Microsoft’s account recovery process for that account.