Happened to a friend. Actually some scammer chargeback him which left negative balance in his account. Paypal notified him to make the balance at least $0.00 otherwise they would ban his account in couple of days.
In your paypal account if you face a chargeback and at that time if you dont have that disputed amount in your account then it will show negative balance(example: -$98) that means you dont have that balance in your account at that time.
I don understand the term negative balance. how could it happen? paypal holds all our accounts and financial aspects. Only if i deposit in my account i could withdraw my money. but with no balance these stories are just folly.
It happens to many, just like using credit card in bank. I have heard about this from many people reporting that they have negative balance in their account. you should have some controls over your hand to avoid this.
You can have -balance if you had chargeback or something that needs much money than your paypal account balance has.I`ve heard that - balance will disappear after one year but i dont know if it is true or not.