Parcel not delivered but tracking says Delivered (LOST PARCEL)

I contacted the courier guy to change the contact number since the phone number logged by the sender was unavailable (lost). the number was changed successfully this is on Monday the 18th of May, on Tuesday afternoon the 19th of May I receive a WhatsApp text to the updated number informing me about my parcel delivery that's on the way however the day ends and I don't receive the parcel. Today the 20th of May I Track my parcel since there's been no communication since the previous day, which was via WhatsApp, I find out that it says the parcel was delivered but I was not the receiver and no communication was made with me besides being told that the parcel is on the way. I've made several calls to the courier guy support line explaining my story to each consultant without any assistance, I haven't been contacted and I still don't know where my parcel is