UPDATE
I managed to resolve this with the chat advisor. They updated my old inaccessible email with my new one that I have access to.
Steps were:
Navigate to where you raise an issue and I put the topic as linked accounts. Put battlefield 6 in the game and your platform. I just put cant link account in the description. Once you have submitted this scroll down and you will find a link to the advisirs via chat
Once connected I explained the problem. You will need to verify security information for your EA account and your platform (psn/ xbox). Email address, dob, last 4 digits of payment method etc.
Once he had all this he reset the email on my old account. He sent verification link and it's all sorted.