How do you determine the correct PIN code of your place in Noida?

I have just started living in Noida, and oddly enough, I continue running into a bit of a discrepancy on an everyday basis, as part of which two different PIN codes apply to my location. For instance, my electricity and gas bills say one PIN code, while the restaurant that I have as my next door neighbor, has a different PIN code. Upon using GPS, I get the PIN code that the restaurant shows as well, and it is also this same PIN code that I use to have stuff from Amazon, and food from Zomato, delivered to my place. At the same time though, I suppose it’s also hard to ignore documents as official as IGL gas bills and PVVNL electricity bills. What should be my PIN code?