Steps:

Open Microsoft Store:

Press Windows Key + S and type Microsoft Store.

Open the app and check for updates by clicking on three dots (more options) > Downloads and updates > Get updates.

Try Reinstalling Paint:

If the update didn't work, go to Settings > Apps > Apps & features.

Scroll down and find Microsoft Paint > Uninstall.

After uninstalling, go back to Microsoft Store and search for Microsoft Paint to reinstall.

Reset Microsoft Store:

Press Windows Key + R, type wsreset.exe, and press Enter. This will reset the Microsoft Store cache.