Provision and Contingent Liabilities

Hello Sir,

I would like to ask for the construction obligation whereby it has the practice of creating a valid expectation.

For eg, I did not state in invoice whereby I will allow the customer to refund the goods to me if those goods are faulty. However, by practice, I usually will refund even I didn’t state in the invoice.

In this situation, it is considered as provision OR contingent liabilities?

Thanks sir