Does your daughter use a Microsoft account to log in to Minecraft (purchased after Dec. 1, 2020 or migrated from Mojang)? ^AM

Yes, we get her the PS4 on the 3rd feb 2021, We have followed microsofts instructions, delete all saves, delete the game, reinstall the game, and it still doesnt work, last night i finally reset her PS4 to see if this helps, not sure though as not been upstairs yet.

Since PlayStation uses a Microsoft account to log in to Minecraft, you will need to continue working with Microsoft Support to recover the account. You can contact them at nitter.vloup.ch/xboxsupport or support.xbox.com ^AM

it would help if microsoft joined the convo, as currently they are quieter than a church mouse

Since you indicated this is an account issue, you'll want to reach out to them directly for an account recovery, as they may not to respond in this thread. Be sure to mention the issue is with the Microsoft account, and not the Minecraft account. ^AM

we want to be able to remove the account from minecraft, as we created a new one, and we want to connect the new one,

Once a Microsoft account has been linked to a PSN account, neither of the accounts can be associated with a different account. Unlinking accounts will cause your purchases to be returned to the original Microsoft account and will no longer be available on the PSN account. ^AM

this we dont care about, she just wants to be able to play minecraft online, and at the moment she cannot

For assistance with unlinking your PSN and Microsoft accounts, please reach out to PlayStation Support: bit.ly/3c8g2qJ. You can also check out our FAQ for Minecraft for PlayStation here: bit.ly/3OH4aus. ^FF

so this is a little pointless,  Even after unlinking, Microsoft and PlayStation® accounts can only be re-linked to the original account. the original account as i mentioned was hacked, this is some poor service, not being able to unlink an account and use a different one