"Your account is not on PIN hold." I think this refers to me as I've never had any earnings from adsense as I've never actually used it.
"Your payment address is not valid." This could be my situation but I don't have a button that says 'Verify address', and I've updated my address a few days ago.
I imagine there's either a bug in their software or old unused accounts are frozen and there is no help text or help file to apply to this issue.
Thanks for the help though.