Eriobotryia japonica, or loquat, is probably what you've got. It is hardy, but unless you live in a very mild area of Britain, unlikely to ever produce fruit. When and if the fruits appear, they do so at the start of our winter, and in warmer climes mature and are ready for harvest the following year, so unlikely to happen here. The growth habit is rather spindly and they do often have bare stems for halfway down the plant. You can try pruning it back in late April, early May, to see if that will encourage stronger growth.

thankyou

The problem could be to do with magnesium or potassium deficiency. The problem first shows itself by causing older leaves to dry up and fall off, so it would seem that it only has leaves on the top of your tree because these are the newer leaves that haven't YET dropped off.

I doubt that it will produce fruit for two reasons:

1. Plants grown from seed will rarely produce fruit, and if at all they did, they would probably be nondescript as commercial fruit trees are grafted from known cultivars that will produce clones of the donor fruit tree. For example, I like to graft fruit trees and I know that apple has a 10,000 - 1 chance of coming true. If it did fruit at all it would probably revert back to a crab apple if planted from a pip. I dont know the chances of Nispero, but I would guess it would be around the same, give or take a few thousand.

2. I don't know what area you live in but unless you live in the South West, i.e. Cornwall, I'm afraid as Bamboo suggested, Nispero are unlikely to ever produce fruit in England.

Hope this helps