According to
Coinbase Assets, in order to complete the code upgrade,
Coinbase intends to suspend PolygonPoS transactions and sending and receiving services from August 26th to September 10th. Coinbase reminds users not to deposit PolygonMATIC, VOXEL, USDC, CBETH and WETH into Coinbase during this upgrade. MATIC and POL on Ethereum are not affected. Updates will be provided when services are restored.