I don't know nearly enough about your flock to be able to tell you why they are not laying. So they are about a year old. How many do you have? What is their laying history? Did they lay last fall or through the winter? Did you supplement the lights? Are they confined or do they free range? Have you noticed a lot of feathers flying around like they are molting?
There are a lot of different things that can cause them to stop laying or not start laying. Molting is the biggest one. Lots of things can cause them to molt, even out of season. A big one is a reduction of the length of their perceived day. That normally is in the fall when days get shorter but have you had a security light or street light go out that may have shortened their day? Did you recently stop supplemental lighting? Has something messed with their length of day?
Stress can also cause a molt any time of the year. That stress might come from running out of food or water for an extended period of time, a predator scare (even if you don't know about it), changes to the coop or run, adding or taking away flock members so the pecking order is messed up, and many other things. Even if it does not trigger a molt these stresses can cause them to stop or greatly reduce laying for a while. It usually doesn't last that long for all of them unless it triggers a molt.
Other than a molt or stress, probably the biggest cause of them not laying is that they are hiding a nest on you. Even if they are contained they can be remarkably good at hiding a nest in the coop or run. Although Easter is past you might want to go on an egg hunt.
Another possibility is that something is getting the eggs. Many predators will leave clues behind if they are eating the eggs, egg shells or a soggy mess in the nest. It is possible the chickens themselves will clean up any broken egg shells but not always. The things that normally do not leave evidence of egg eating are snakes, canines, and humans. Where you are it's not going to be a snake this time of the year, besides snakes are inconsistent. They eat a few eggs and disappear for a few days while they digest them, then come back for more. I've experienced that more often than I like to think about.
Most canines like coyotes or foxes would probably be more interested in the chickens than the eggs but often dogs will leave the chickens alone yet eat eggs. Do you have a dog that has access and has learned that the egg song is an invitation to a snack? I'll let you think about the human possibility.
So what can you do? Can you lock the chickens in the coop and/or run for a few days? If you start getting eggs you know they are hiding a nest or you locked out a predator. At least you know they are laying. Or make a mark on an egg and put it down there. If it disappears you know something is taking them.
I've had pullets skip the molt their first winter and lay all through winter, no supplemental lights and occasional temperatures below zero. Days were a lot shorter than 14 hours. I've had grown hens start laying in the dead of winter after they finish their molt. I've had hens not start laying until the days get longer and warmer. Each hen is an individual in this. Basically they are going to lay when they lay. That can be frustrating.
When a hen is ready to flip over to egg laying mode, it takes a while for her to get ready. She has to change her internal plumbing. She has to grow ova big enough to become egg yolks. Don't expect to flip a switch and you immediately see eggs unless she is ready to start anyway.
If it were January I'd suggest you extend the lights some to start those triggers, but this late in the year I would not do that. The sun should take care of it. It's been a cooler winter and delayed spring, they may be waiting on consistently warmer weather. What are you feeding them? A higher protein diet can help get them to laying. I feed mine a 15% protein feed and have plenty lay in the dead of winter so I'm not as sold on this as some people, but I do believe it can help. Before they start to lay they need to build up some excess fat so they have that in reserve, so a few high protein treats, especially BOSS (Black Oil Sunflower Seeds) can help. Don't overdo them, the Oil in BOSS stands for oil. Like any other treat, feed BOSS in moderation. But an egg yolk is about 1/3 oil and the oil will help them gain that fat reserve they need. Oil is an essential nutrient.
That's enough typing, hopefully you made it to the end. If you can tell us a bit more about your situation we may be able to be a bit more specific, but maybe you can get something out of this that helps. Way too often, patience is your best friend in these situations. Good luck!
