OmniTechRetail — Did not receive hard copy of the invoice and none was sent to my email, and there was no option to download it on my orders

I purchased a Dell 27 monitor (S2721HN) from omniTechRetail. I was not given an invoice and no invoice was sent to me to my email. recently the product I bought developed a problem and the company is requesting an invoice issued with the product. I am requesting that u send me a new invoice on my email so that I can download it. My order number is OD[protected]. I tried contacting Flipkart and omniTechRetail but there is no response coming from them.