Byjus — not taking back the byjus packages

Address:

gomti nagar,lucknow, Lucknow, Uttar Pradesh, 226010

I bought 3 study packages from the byjus but i wasn't satisfied with the service. So, after that i called them and told them many times that i want to return the 3 packages, time went on and no action was taken and now they are saying that the policy of returning back is of only 15 days after you have buyied the product, so, what should i do as they are not taking any action.