Changing the Polygon network RPC may help you. You can do it via chainlist. Remove the 2 spaces I inserted in the link.
https:// chainlist. org/
Click the arrow below the the Polygon network box on Chainlist. There you can find a list of RPCs. Choose one at the top of the list and add it to your MetaMask wallet.
The following article is related.
Please do what I have suggested above. Let me know how it goes.