It was likely sent as an echeque because your account was in the negative.

Basically PayPal have seen you as a bit of a liability with having the negative balance so they don't want to upfront the money to the seller without those funds clearing the banking process.

It's a bit of a catch 22 you're in but it'll resolve itself before long.

Echeques can take a while... I believe 14 working days is stated as the max time for it to fully clear.

So whilst yours could have cleared on the 7th, it could still take a further 5-7 working days for it to then be deposited into PayPals bank account.

Your negative balance will be cleared the second it hits PayPals bank account.

I know it seems like such a long time, but banking processes are notoriously slow.

You could very likely have a few more working days yet before this is all cleared up.

As soon as your negative balance has been cleared, the seller will have received their payment at the exact same time.