Recently(Maybe correlated to EIP-1559 upgrade) matic transactions that would previously work have stopped working for me, even basic ones like transferring native currency. These transactions still work on other chains(tested on bsc).
Here's and example of code that won't go through for me.
Account = new Account(PrivateKey, 137);
Web3 = new Web3(Account, "https://polygon-rpc.com");
var transaction = await Web3.Eth.GetEtherTransferService().TransferEtherAsync(sendToPublicKey, .1m);
an example of a transaction returned from above is: 0xc12b1d990d7a8a512e8b39e659777db92d4afde9ceb14562ddab8a9c17a18601
the returned transaction has a status that include
This txn hash was found in our secondary node and should be picked up by our indexer in a short while.
some eventually disappear and can no longer be tracked.
I've tried both EIP-1559 and legacy transactions.