I think what you are saying is that the tree fruited heavily previously, lost its leaves last summer, and this year is not fruiting at all. If that's the case, it sounds like it had a shock of some kind last year while becoming established, perhaps from getting too dry. Did the 'lots of fruit' you got before come from flowers already on the tree when you bought it two years ago?
Losing its leaves (other than in autumn) would have given it a severe shock. Hopefully it has now begun to root properly in the soil over the winter. As long as it has leaves this year and continues to grow well without losing them, you should have blossom and fruit next year.
The only other explanation could be if it flowered this year and all the flowers were affected by a late frost so no fruit got set.