Trying to change E-mail address

Hi,

I’m trying to change my E-mail address online and / or in the ‘app’, but when I put in my new E-mail address it says the E-mail address has already been taken. When I request a new password for that E-mail address I don’t get an E-mail so not sure how I can change my E-mail address.

Any advice?

Thanks!

Raf.