If you cannot smell your perfume after an hour, it has faded or worn off.
Olfactory adaptation is the neurological process by which your brain reduces its response to a constant, unchanging stimulus. If the scent is present and unvarying, your brain progressively filters it out — not because the molecules have left, but because constant scent carries no new information and the brain allocates resources accordingly.
Other people can still smell it. You cannot. This is not a longevity failure. It is a perceptual one. The perfume is there. You have simply adapted to it.

WHAT TO DO INSTEAD
Step away from the application site for 60 seconds. Smell your sleeve or the inside of your elbow — areas where the scent has drifted but is not the point of direct application.If the scent is still present, the formula is performing. Never be afraid to ask your friend to scent you!
Do not re-spray on top of a formula that has not faded. Layering over an existing application distorts the Three Acts sequence of both. Reset the nose. Evaluate fresh.