EA linked to non-existent Twitch account

Been keen for BF6 twitch drops and maybe early beta access. So I've tried to link my EA account to my twitch however I get greeted by the message that my EA account has already been linked to an account under the name of 'H6jqg3VF4tGZqDm'. While it is a strong password if anyone wants to borrow it, it is in fact not my twitch account. I'm not sure if my account was hacked before my 2fa was set up and someone used my EA account for their twitch (seems unlikely) or I've linked an account many many years ago. Either way EA policy means i cant use my current working twitch because of this mystery account.

I've tried a few times to get a ticket raised yet nothings showing up on the my cases tab on EA help so figured this is my next best option to try and remove this link to allow me to link my current twitch account. 

Thankyou in advance for any help,

Wiltaaar