Delhivery seems to be leaking numbers and performing fake COD deliveries and then asking for cancellation OTPs. What is the reason for this ?

A few days ago, I had received a call from somebody from Delhivery saying that they have a delivery for her. They told that it is cash on delivery and were asking for payment. They did not know my name or address when they had called. The next day, they called again. This time, they found out the name, but did not know the address. They were asking for the payment again. Meanwhile, Delhivery sent a whatsapp message from their official business account, containing an OTP which has to be shared to cancel the delivery. I know it is the official account because the same account sent messages when I made genuine orders, fulfilled by them. Since I don't know what the OTP was for or even what the parcel was, I advised did not to share the OTP or any acknowledgement that we made such an order. I checked with family members and none of us made such an order. I searched on Google and Reddit and found there were few other such cases of cash-on-delivery scam. Till I received an official message from Delhivery, I thought it was just a prank call or something. It was quite concerning when they sent an official message with an OTP. The OTP was to 'cancel' an order I never made, so I did not share it. I am wondering what is the reason for this scam and what are they trying to do. It's also concerning that Delhivery is leaking numbers and addresses like this.