Understanding fading
Why do sweet perfumes fade quickly
A sweet opening can feel prominent without establishing lasting projection. If a sweet perfume seems to fade, distinguish the loss of its initial sweetness from a quieter later scent or reduced awareness of the fragrance.
A HUME Fragrance buying guide

Name the sweet character
Vanilla-like warmth and sugary fruit are different impressions. Record the particular quality you miss later rather than assigning one behavior to all sweet perfumes.
Track enjoyment and presence
You may still enjoy a warmer trace even when the opening changes. Conversely, a remaining sweet impression is not useful if you no longer like it.
Avoid automatic extra application
Follow product directions and consider the setting before adding more. A repeat wear provides clearer evidence than several immediate top-ups.
Try this before you buy
Write what became quieter and whether another enjoyable impression remains after the opening.