First of all lodge compliant addressed to MD of the company with a copy to Nodal Officer if any, and demand refund of your money with interest, collection of T shirt from you at its cost, or supply iphone as promised by it….
Have you saved the screenshot of the offer made on your computer screen, on line form submitted by you, payment transferred by you???
Did you put any remarks on run sheet of the courier that instead of iphone cover contained T shirt? Did the packet display any declaration on contents in the packet?? Do you find sticker of the courier on the packet showing AWB bill number???
You may also submit a communication addressed to local BM of the courier that instead of iphone you find T shirt and you have properly agitated to delivery boy, and Courier Company should supply you the declaration which courier demanded and company signed on contents of the packet. Meet the BM and obtain a communication even if by email/letter on plain paper with seal of the courier that it supplied T shirt.
You will have to agitate properly and in writing and thereafter you may lodge a police complaint and complaint with DCDRF.
Avoid on line purchases, on line payments and do not get lured by such unscrupulous and fraud companies. It shall be appropriate to contact a local lawyer for expert opinion, and issuing legal notice.
Why should any company offer iphone for Rs.999/???