you need to provide more information!
start with how exactly did you use "used replace-by-fee"?
when we say RBF you need to have set it already on your transaction before sending it, if you haven't already then you can not use RBF anymore. and if you have then using it is as simple as going to your history tab and using the bump fee option by right clicking on the unconfirmed transaction to increase its fee
are you sure you used RBF and not create a new transaction and send bitcoin twice?
when you say your balance is zero now, how much should it have been?
when you increase your fee you use your other funds to cover the fees. if you had a huge transaction but a small leftover in your wallet and increased the fee a lot you might have spent all of it. or it is possible that you had a small amount and after increasing the fee your leftover was smaller than dust limit so it was spent as fee also.
start with how exactly did you use "used replace-by-fee"?
when we say RBF you need to have set it already on your transaction before sending it, if you haven't already then you can not use RBF anymore. and if you have then using it is as simple as going to your history tab and using the bump fee option by right clicking on the unconfirmed transaction to increase its fee
are you sure you used RBF and not create a new transaction and send bitcoin twice?
when you say your balance is zero now, how much should it have been?
when you increase your fee you use your other funds to cover the fees. if you had a huge transaction but a small leftover in your wallet and increased the fee a lot you might have spent all of it. or it is possible that you had a small amount and after increasing the fee your leftover was smaller than dust limit so it was spent as fee also.
Okay no problem! I used the RBF function as you have mentioned, I right clicked on the transaction then replace-by-fee and dragged the fee tool to max, would this have spent the full amount? The balance had been showing around 80 euro worth of btc which was 'Unconfirmed'. The balance had been zero prior to this. I don't think I created a new transaction however after looking on Blockcypher it says "This transaction had an attempted double-spent but was still confirmed". I have sent the transaction to ViaBTC accelerator as mentioned in the post above. Very grateful for the help!