nitasha212,
Thanks for following up with us. Let's continue working together to find a solution.
Next, did you check to be sure your MacBook Air is updated to the most recent software version, which is macOS Big Sur 11.5.2? Learn more about updating your Mac here:
Update macOS on Mac
You'll also want to try cleaning your MacBook Air with the steps in the 'Notebook computers' section of this support article:
How to clean your Apple products
Clean your Mac computer’s screen or display
If that doesn't seem to help, are you experiencing this behavior in any other apps? Let's boot up in safe mode and see if the issue persists there. Learn how here:
How to use safe mode on your Mac
Let us know how it goes.
Take care.