I can't make a transaction anymore

I tried to do a SWAP in DFNY using Metamask, but the transaction was too slow, so I cancelled it.

However, the cancellation was not executed in Metamask, and when I try to do SWAP in DEX after that, it shows “Unexpected issue with estimating the gas. Please try again.” I can’t do any transaction at all.

How can I solve this problem?

Thanks for reply.
Finally, I solved the problem by restarting the computer.