I’m cancelling the flights myself
Situation A
I bought flight tickets, but I have to cancel them as the dates are not appropriate after all. The seller’s terms and conditions state that a customer can cancel the flights free of charge for any reason and get their money back, as long as the cancellation has been done in time. However, the seller does not agree to make a refund."
The customer has paid the online purchase with a credit card. Therefore, the customer can dispute the transaction by filing a complaint with the bank. The customer should dispute the card transaction and send the order confirmation and contact to the seller as attachments so that a potential breach of the agreement on the seller's part can be confirmed.
Situation B
"I bought flight tickets, but had to cancel them due to illness."
The customer has paid the online purchase with a credit card which includes travel insurance. The customer should file a claim with the card insurance provider.