If it's new authentic HP it may say "Warranted for Cartridge Life"
see back panel, on the box. Back panel says "See enclosed leaflet".
Inside there is a leaflet saying until the toner is depleted.
HP replaced one for me, no purchase receipt asked for, because
there were grey streaks after about 3 mths of light use.
I'm in the UK, I had to send it to Norther Ireland, and the
replacement was shipped from a dispatch facility in Rugby.
I had to twist their arm though, expect a runaround.
They know if it's full or empty, and how much use, from the weight.
A full cartridge has one weight, empty another, the full service
manual for the printer gives these weights.
Check to make sure that all packaging was removed from the toner. Some
cartridges have a plastic strip that needs to be removed. On a few of
those the grip will tear off, leaving the strip in place. The printer
will continue to print with whatever residual toner is in there, but
keeps getting lighter.