When you try to mint your NFT, you may get the following error - Unknown Processing Time. It’s usually because the gas fee limit is set up too low. To solve this issue, you need to first click on Edit.

Then it will bring you to this page, click on Edit suggested gas fee.

And you will see the error here…

Try a higher gas fee for both the Max priority fee and the Max fee, like 40 or something, and click on Save. And it should be resolved as follows:

Note that the gas fee is fluctuating, so you may need to change it once in a while when the error shows up again.