On the 4th of September 2024, Polygon upgraded MATIC to POL. Do not worry - your MATIC on Polygon is safe, it will be automatically converted to POL.
Regarding other networks on which you have MATIC (Ethereum, BSC, Gnosis) - please, exchange it on other resources, since it will not be upgraded to POL automatically. Kindly note that you will not be able to use MATIC for network fees.
We have also added POL support to Ethereum, MATIC is still supported there and on other networks as well.
Also wMATIC will remain on Polygon, we will add wPOL in the future.
You can find more information here.