Looks like woolly aphids. Quite difficult to get rid of by spraying etc as the "cotton wool" forms a waxy style protective shelter for the little blighters.
If your tree is only 3 years old and not too large I would consider spending an afternoon with a bucket of soapy water and nail brush scrubbing off every little bit you can see. You could then consider a protective spray of insecticide (but late in the evening after the pollinators have gone to bed).
You then need to be vigilant and remove any new patches when they first appear. Laborious to deal with - I have it on some eating apple trees.
No fruits last year may have been due to the aphids but might also have been due to the weird weather - we had blossom very early (before the pollinators were out) but also quite severe frosts when everything was in full blossom - poor yields as a result.