Cookie issue from firefox import

I work in a Uni and use Jisc for some work. I’ve been using Brave for a week now without issues until I had to log into the Jisc website and I keep getting an access denied message. I instantly presumed it was an issue their side, but after a few angry emails and getting no help from them (What is brave, I don’t think we support that etc…) I realised that Brave works just fine in Private Browser mode. I guess here, the issue is from importing all my bookmarks and cookies over from Firefox. The problem is I can’t seem to clear this or even click the logout button on their site (Might be some issues with their logout code too I guess).

Their website is https://community.jisc.ac.uk/ (I log in using the institutional login)

I need help with clearing a specific cookie please.
I could probably nuke every single cookie and password that’s saved but this brings an incredible amount of inconvenience to the point I’d rather just continue to use my old browser (Which has an option to search sites/cookies and delete selectively).

Am I missing some option or is there something else going on here with the original import that’s causing this issue ?

(The logout button also works fine in private browser mode, so the issue seems to be an imported cookie that I can’t seem to selectively remove)

Just in case this reply helps other new users… I found a tiny icon near the address bar, that shows you site information. After clicking this, it shows the site cookies and you can selectively delete them from there. This resolved my problem. However, perhaps this should be a searchable thing in the browser general options too ?