I looked at the picture. Diagnosis is difficult from this far away but:

1. It looks like the tree is indoors. Even in the UK this tree should
and could be outside most of the time. You can get away with being inside
for a time but sooner or later it takes its toil on the plant.

2. Watering might be the problem. Either too much or too little. Did
I see a lot of moss on the surface. This might mean too much water or the
water might not be getting to the roots. We recommend the Perisano (sp) pick.
Put a wooden chop stick or meat skewer in the soil about half way between the
trunk and edge of the pot. Water when the skewer feels dry to the touch.

3. Pull the tree and look at the roots. White, fleshy means healthy,
black, mushy means sick.

4. Although it doesn't look like it from the picture, this could be a
reaction to an early fall. (Also I thought you guys were having a heat wave.)

Billy on the Florida Space Coast

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