For the benefit of others because it is largely too late for OP:

1. This yet another example of why trading with opaque third-party vendors is a poor idea. This in ordinary non-pandemic times as well. In this particular case, OP used an enterprise located in the Netherlands to issue tickets on a German carrier for transport between Canada and India. He presumably has a credit card issued in Canada. That makes the situation doubly worse. In addition, it may be that he did not carefully review his contract with the third-party before purchasing.

2. If OP happened to be due a refund for the full amount paid and it was not forthcoming, he missed the easiest form of redress, e.g. a chargeback dispute through his card issuer. While better established issuers allow up to a year even though not legally required to do so, tempting fate by missing the legal minimum can, as it did here, lead to poor results. There is never a reason to delay a chargeback. Wait the required time period and then act. Nothing prevents you from continuing your dialog with the third-party and as soon as you either have a full refund voluntarily issued, you may always withdraw your chargeback.

In this case, it is likely that OP agreed to the fees. But, if he did not and the third-party owes him what he thinks he is owed, he is stuck having to sue and it is unclear whether he can reach the third-party in Canada.