Your plants are growing, that's a good sign! They are going to need more space, it is time to assist their growth with a bigger pot.
The roots are coming out on all sides, the pot is visibly too small, the leaves are turning yellow, the new leaves are smaller, it's time to repot your plant - in 5 steps.
Repotting must be done every 12/18 months around March/April
You will need :
your new pot, ideally 3 centimeters bigger
a pruning shears
paper to protect your floor (use your Janvier bag for example !!)
You will have watered (ideally) a few days beforehand - recommended but not mandatory.
Prepare your new pot, by lining the bottom of the log with clay ( 4/5 cm), add a generous layer of fresh potting soil
(adapted to your plant) to cover the logs.
Protect your floor for repotting! While pressing on both sides of the pot if it is out of plastic, or while removing the compost on the surface and by tapping the bottom if it is in another material (one cuts possibly the roots which would have left by the hole of drainage), one then draws then very delicately his plant.
The old potting soil is scraped off (about 1/3), the damaged roots are cut off with pruning shears and the plant is placed in its new pot.
Add fresh potting soil all around the plant, using your fingers to gently pack it down to hold the plant in place. Leave a few centimeters between the surface of the soil and the top of the pot.
Water generously but delicately, no need to add fertilizer :)