You haven't mentioned repotting - if your tree has been in the same pot for five years, it will most definitely be potbound - this affects growth eventually. Turn it out of its pot and check, pot up into a larger container.

Thankyou for reply, but I did repot it two years ago, have another one conical shaped and this one is looking very healthy, so maybe I should consider repotting again.

I have had one for ten yrs.
I have never changed the pot size so I know it is pot bound.
The same thing happens to mine. I have to water it copeously, ie a watering can full of water every couple of weeks. They do not seem to be affected by over watering. Every couple of months I mix a general feed with the water. New leaves should soon sprout.
Good luck.

Blimey, Waterboy, a can every two weeks - doesn't sound like anywhere near enough to me, lol, I water contained plants every week. Overwatering isn't possible provided there's drainage in the pot and its not standing in a tray.

Rachel18, I assume you've inspected the trunk, branches, stems and leaves for any signs of disease or infestation? No scale, or white fluffy bits, or leaves stuck together anywhere? If nothing, check the rootball - and the compost, there may be invaders in there such as vine weevil or root aphid or other.

Thanks, will check the rootball and will keep fingers crossed. kind regards.

Hi Bamboo. Its worked for ten yr. However drainage is very poor due to the root ball I assume

Yes Waterboy - in the end, there's much more root than compost in the pot...

I think it is all root.
It seems to survive on the water and the odd feed