The man at Cashify needed my mobile number to send me my receipt. 
“No, you don’t,” I said. “Once you guys get a person’s mobile number, you start sending them your 
junk messages.”
“We send zero messages,” he lied with a straight face. “See, my number’s on Cashify’s database and I’ve not received one message.”
“Listen,” I said, my ire mounting. “I’ve paid for my second-hand phone now and I have the product. Just print the damn receipt.”
“We don’t have a printer,” the fellow said. “And the transaction cannot proceed if any required field is blank.”
“Take my email address,” I said. He took it. 
“The phone field is still blank,” he said. “Shall I use my phone number?”
“Whatever.”
“The receipt and warranty would be in my name, not yours. You ok 
with that?”
He eventually won by exhausting me. 
The first of many Cashify messages came a week later. Please rate your shopping experience.

Cashify is a small player in the big game of driving people berserk with torrents of messages, a worldwide phenomenon in which India, with 7.6 billion daily spam messages, takes third place after China and the USA.