did you have any late frosts? this often puts paid to fruit formation. as would weather conditions that reduced the number of pollinating insects at the time the flowers were out.

It may be doing a turn of biannual fruit setting. A lot of fruit trees do this, especially as some varieties are prone to it. Prune of any extensions back to 3 leaf axils if the tree is small enough to reach, so it doesn't waste energy growing long shoots (summer pruning) now. In February nip off top shoots and cut out any wandering shoots getting too long (winter pruning). Then at blossom time, if you have the patience, and can reach, take out about half the buds at white bud stage. Don't forget to feed too. It might work!