1] Some quails take longer.
2] There might not be enough lighting. You might have to add lighting near their cage and put the light on from 6pm to 9pm to give them extra daylight hours.
3] Female quails have to feel safe and are relaxed before they start laying eggs. Make sure there is no disturbance causing them to feel unsafe, such as barking dogs or cats near their cages. Don’t move them around.
To make them feel safe provide some ‘hiding’ place, maybe a box with a ‘roof’ but open on one side.
Adding a ‘dust’ bath helps relax them.
4] Maybe you are over-crowding them in a small cage.
5] Quail love extra protein so make sure to feed them bugs if you find them. earthworms, flies, even ants you catch in the house can be fed to quail.
6] Also give them extra calcium by way of crushed chicken egg shell, sterilized in a oven.