Depends entirely on the fare basis (which is difficult to check without using paid-for tools like KVS). In some cases there's a fee for no-showing but not for cancellation in advance. For example, LH's fare ZRCGB from the UK to Asia allows cancellations at any time (including after departure) for £200, but changes can only be made before departure (also costing £200).

So if the OP can post the exact fare basis of his ticket then we can look into this further.