Flipkart — exchange of moto g6 for new phone

I ordered a Google pixel 3a from Flipkart and put my Moto g6 for exchange. First of all they were supposed to deliver by 11 am but it's not done. I call the delivery boy and he says he can't come before 1 pm. I call the customer service ( which I could only get through after 4 tries) and he just reads delivery instructions as on the order screen?

I try reaching the delivery guy again and he doesn't turn up till 5pm. After he comes he first starts shouting at me asking why I clicked the delivery deferal message when he told not to? The message stating that the delivery will be delayed?

Anyway I hand him my Moto g6 he says he can't accept it because there is a small white scratch on the back cover? Which is literally a spec. I say that's not fair because the instructions on the website [protected]@a otherwise.so I ask him to make me speak to the manager after saying "dimaag kharab Kar rahi hain" and the manager starts abusing me on the phone and threatens to raise a complaint because I'm detaining the delivery boy? After this the Flipkart customer care executive asks me to wait till Friday with no resolution? She doesn't understand the problem and start raising her voice against me?

Do you want to make sure customers don't order form you?because I'm not anymore and I will make sure no one around me does.

Even though you're a pseudo homegrown company( since you're registered in Singapore for tax benefits) I will always order from Amazon. They are upfront about their orders and understand the customers