failed bank transfer put me in negative balance, paid in funds from bank but bank got charged again

[MikeClark]

Paypal have charged my bank twice for a transaction.

I woke up to this email one morning.

"There wasn't enough money in your bank account ending in **00 to cover the below payment you sent."

As a result, we debited the amount from your PayPal balance.

Your PayPal account balance now shows an amount owing to us. Please restore your balance at your earliest convenience.

We may reattempt to charge your bank account. Please ensure that you have enough money in your bank account to cover this payment and avoid any penalty fees that your bank may charge."

So i sent two transactions from two accounts to cover my account.
each transaction was £80. With one purchase using what was left over this then put me back at £0.00. If i'm essentially using my bank to pay back the money i've borrowed fromm paypal, that's the same as paypal charging my bank for this purchase again. WHY HAVE I HAD TO PAY TWICE 

[kernowlass]

@MikeClark 

If you have failed bank transfer then Paypal automatically keep trying to access those funds to clear your negative balance.
They have already fronted the payment to the seller on your behalf and so want the money owed.

If you sent a bank transfer to your Paypal account and Paypal also automatically applied for the funds as well then you would have 2 payments processing to your paypal balance.
The first one to arrive will clear the negative balance and the second one will be credited as a + to your balance and you can withdraw it back to your balance once cleared.