Thanks for all your replies. I think I have worked out what the problem is. I received an email for me to verify the new withdrawal address but I only just saw the email and the link expired after 60 mins so I can't verify it now. Currently on the phone with them here, hopefully they will be able to sort it for me.
I've used Kraken a few times, and don't worry, it's a good exchange, very safe
I don't remember having to confirm my e-mail address in order to withdraw, but I do remember that I had to first register the withdrawal address, confirm it by e-mail and then that address would be authorized for withdrawal, without needing any other confirmations when I wanted to withdraw my balance in the future
I never used Kraken's phone support, so please update us and let us know if they provide good customer service
And finally, I don't think you even needed to contact them, you just had to re-register your withdrawal address, confirm it and then make the withdrawal