A buyer claimed that goods were defective 6 weeks after the sale.

In robust language, they demanded a refund by Paypal. So I tried to initiate the refund.

But my Paypal balance was too low, so it is no go.

Paypal say I must add funds by setting up direct debit from a bank account, which takes 3 to 5 days!

Why is this? If I buy something with nothing in my account, then Paypal charged to my credit card which is registered in the Paypal account.

So the buyer is the victim in this, not getting the refund in a timely manner.