Why my txs always not confirmed?

Hello, moralis team!

Why my txs always not confirmed??

At first, I can found then in the mumbai.polygonscan.com,like this:

But they are always pending, and then after several minutes, they will disappear, like this:

And the error message from web3js is "Transaction was not mined within 750 seconds, please make sure your transaction was properly sent.”

I’ve not found this problem before at a free plan, now I have signed up a new account, with pro plan

Please tell me the possible reason,


This is not related to a plan. I think that I saw this happening before. For example if you reuse an old nonce then this may happen. How do you send those transactions?