Tesco Bank System issue

It seems that Tesco Bank's system remembers you even though you closed your previous account over five years ago. Whilst attempting to open a 5yr Fixed term account, the system decided to present me with a Christmas advert pop up and cancel my application. It had just decided that i was an "existing" customer not a new one. I phoned them but they want me to log in and update my security details before allowing me to continue the application. I cant do this because they insist on sending the log in link to a phone that no longer exists. My last employer repossessed it when i retired six years ago. So I am stuck. Its a shame that systems cannot recognise a new application, or that the details they held five years ago are considered to be so accurate now that they would refuse a large savings deposit over them, or that they cant be more helpful. So it seems Tesco Fixed term accounts are not available to existing customers, and anyone else who has ever had a Tesco account, a clubcard or anything else that caused them to create an account for you..