Help linking ps4 to current pc account

Help I have just brought final fantasy online for the ps4 and I want to link my current pc account to it but an old account keeps blocking it and it would let me change the id for it please can someone help me on what to do

to add to this I have delete the old account but the old id keeps appearing

Have you played FFXIV on that PSN account before? A PSN can only be linked to one FFXIV account and cannot be unlinked in any way

No I only played it as a trial on ps4 until I had the money but a friend brought me the game last year on a new account and all my data and expansions is on there

So to be clear:

You're using an entirely different profile/PSN account than you did for the trial right?

No the psn I currently have i want to link it to my current account on pc but it's link to a very old account to try the game out and I forgot the details

So I thought deleting that old account would fix it guess not i don't really want to pay for two subs just want to pay for one sub on one account that's got all my expansions on

Well then you're out of luck.

Once you play the game on a PSN account, the SE account you logged in to play on is permanently linked to that PSN and cannot be unlinked.