There is a slight mismatch in the back end of My Account.
I have asked our back office team to de-register your account so that you can register for My Account correctly.
We will post back when they have carried out the necessary work.
Hi @OCE_Arne - I have had a similar issue with logging into TalkTalk My Account too. Before xmas I could access this fine. Tried recently and the system https://auth.talktalk.co.uk/login screen keeps on saying it doesn't recognise my username & password.
Spoke to TalkTalk customer service who couldn't understand why this is, and raised a ticket which I am still waiting a response on 1-000002-800177-0 - hope you can help resolve this asap!