If you funded the original paypal payment to the seller with a debit or credit card then it won't go back to your paypal balance.
Once marked as completed it will automatically go back to your bank account or credit card but takes up to a week to process through to the bank and a bit longer for a c.c (paypal say allow 30 days but I have never waited longer than a week for mine).
Advice is voluntary. Kudos / Solution appreciated.
