It can change, mostly related to health. For example viruses and diseases can alter iris color.

If it’s cloudy and dull it may also be early stage of clouding of your lenses (cataract).

If you haven’t seen an optometrist recently, you may want to get checked, just to be safe, they can rule out any ongoing problems :)

https://health.clevelandclinic.org/can-eye-color-change