Re: Transaction rejected by our node. Reason: Transaction was previously accepted...

That option is greyed out and not selectable.

Restart Bitcoin Core with the -zapwallettxes option. See https://achow101.com/2016/07/Bitcoin-Core-Troubleshooting#option-startup for help with that. It will clear all unconfirmed transaction from your wallet so that you can respend the same inputs.

Cool that fixed it. Will have to remember that if it happens again.