Paytm — Paytm fraud order [protected]

Address:	560075
Website:	www.paytm.com

I placed order no. [protected] on 13th January 2016.Seller(trendin) dispatched order on 15h from courier company named ajexpress on 15th Jan.But after 16th January there is no update on parcel's tracking ID.On 19th Jan I called up paytm to ask for order status but they said it will be delivered by 20th January. But it did not get deliver.I called up again on 21st Jan and they informed it will be delivered by EOD, even then it was not delivered.
I called them up on 23rd, dropped them lot of mails and created Tickets where they responded with a same reply, we will resolve it in 2-3 days and their 2-3 days were never over.
I called up courier company and they said they have lost the parcel somewhere and have informed trendin about same.I called trendin and they said they can not do anything since the order was placed through Paytm.I called paytm customer care again and again to get refund of my money but they never helped me infact they never even tried to help me.
Its been more than 2 weeks neither they are refunding my money nor they are delivering the product.Please help me and guide me how can I get my money back?I have spent more than 300INR in calling them and getting my problem solved.I demand a refund for that too.Please guide me what should I do?