I have problems sending and receiving iMessages on my Apple iPad Pro 12.9 (2022)

Press Settings.

Press Messages.

Press the indicator next to 'iMessage' to turn on the function.

Slide your finger upwards starting from the bottom of the screen to return to the home screen.

Press Settings.

Press General.

Press Date & Time.

Press the indicator next to 'Set Automatically' to turn on the function.

Slide your finger upwards starting from the bottom of the screen to return to the home screen.

Press Settings.

Press Messages.

Press the indicator next to 'iMessage' to turn on the function.

Slide your finger upwards starting from the bottom of the screen to return to the home screen.