u/Fine-Koala-7506

As the title says I have had a loved collection of perfumes I have bought repeatedly but this year I have noticed that the fragrances i have owned and used for a long time have suddenly changed

Somehow the notes are getting muddled? Some have gotten too dull?

And i have used and re bought these ones and I am definitely sure something is off

So does anyone have a clue why it's happening?

Is it the heat?

Is it the storage?

Has anyone else experienced it?

Anything that can be done to prevent this kinda situation?