would help if we knew where in the world or what state you are in as that would narrow down the possibilities.
My hens slow way down laying 1-2 weeks before I actually notice them molting, some of them haven't looked like they were molting either as they did a soft molt instead of a hard molt. Less daylight can slow them down, some breeds are better wintertime layers
than other.
Age of the flock can be a factor.
Nutritional deficiencies.
Internal or external Parasites.
Stress, including by nocturnal predator visitors.
Picture of your flock and set up might clue us in too
