Unable to authenticate account due to mobile number issue

Hi,

I am having an issue that I can't verify my account because in order to verify my account i need to login into my authenticator app which this unfortunately asks for verification so when I choose other means and a text message i get an error that my mobile number is incorrect. I also can't update my security details as it wants authentication which I end up in the same loop of not being about to verify due to the mobile number issue and not being to access the authenticator due to it wanting verification. The help desk were baffled with this issue so sent me here to hopefully resolve it. any help would be appreciated.

Thanks

Paul