The software Bitcoin Core is using?
Then you need to have your software forget about your unconfirmed transaction that is not in the mempool, so you can do it again at a higher fee.
When starting your Bitcoin Core, run it with
-zapwallettxes. This will make your wallet forget about the unconfirmed transactions relevant to your wallet. You can learn how to add that on Andrew Chow's blog.
Then the balance in your wallet must be converted to the balance before making the payment.
I learned this from here, but the other two methods are not applicable as you need to change your transaction to increase the fee.