A forced restart of your iPad may resolve the issue:
- On an iPad with a Home button: Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.
- On other iPad models: Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the top button. When the Apple logo appears, release the button.
If the forced restart fails to resolve the problem, take a screenshot and save this to your Photos:
Take a screenshot or screen recording on iPad - Apple Support
Having taken the screenshot, review the captured image - rotating the iPad 90° to ensure that the image does not coincide with the visible screen.
Is the screen corruption visible in the captured screenshot? If the corruption is not visible in the screenshot, then you have a hardware fault that requires investigation and repair by Apple.
By contrast, if the screen corruption is visible in the captured screenshot, then a software or OS corruption is present. Is so, we can explore possible solutions.