It is probably getting into a sort of dormant state for the winter. Be patient. If it is not losing leaves or leaves not turning yellow, then it is all right. Do not fertilize or fertilize very lightly.

Watering three times a week seems too excessive. Check to see if it needs water by digging
with your fingers a couple of inches into the soil mix to see if it is damp. Alternatively, shove
a wooden skewer halfway between the tree and the wall of the pot and all the
way to the bottom. Pull it out and if you see particles on it, then it does not
need watering.

Thanks. I'll check the watering, we haven't had any rain for over a month with fairly summerish weather, so has looked dry at least.