Complaint regarding convenience fee charged by Myntra

Recently i purchased a jacket from myntra which costed me Rs 608 but i returned it due to size issues. The amount of refund i received was only Rs 499 and Rs109 was deducted by the name of convince fee. This amount is too high. Other online retailers are not charging any of those fee and if they are charging the fee is only Rs 20-30. My hard earned money is deducted unnecessarily. I have to pay extra amount without even being informed about what’s included in this fee. I’m paying about something i have no knowledge of.