According to one answer here: https://www.quora.com/How-do-Islamic-banks-make-money-if-they-cant-charge-interest-because-of-sharia, you have to pay what you owe and the bank can force you to pay.
So what happens if you have to delay your payment or are unable to pay anymore?
Edit:
Ok, I can not comment, so to clarify: if I can not pay, how would the bank usually force me to pay? Is the amount of money I have to pay increased by some fine? Is my property sold off?