The NIE has no expiry date and in normal circumstance last forever, and getting anew passport (with a new number) makes no difference.
I even changed my name and passport, and now have dual nationality, but have kept my NIE. My wife also added my surname to her surname and again she kept her Residencia number (she is non EU so has Residencia)
I have never heard of anyone cancelling their NIE, albeit that people do and have cancelled their Residencia, when it existed, and their EU Citizen's Registration now.
(Not that one should assume) but I 'assume' the NIE stays with one forever.