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If your iPhone or iPad gets too hot or too cold - Apple Support
If the problem does not appear to be temperature related, you might be best advised to seek advice directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page.
Alternatively, you can initiate and manage your support cases from Apple devices using the excellent Apple Support App. If not already installed, the App can be downloaded from the App Store:
https://apps.apple.com/app/apple-support/id1130498044
You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) where the technicians will be able to test and assess your iPad for faults:
Genius Bar Reservation and Apple Support Options - Apple