we have a weeping cheery and the leaves are curled, what is the problem? no signs of insects

Question

I sprayed with insecticidal soap.

Answer 1

It sounds like the tree may have a fungus, but you didn't say whether the curling leaves are becoming discolored or falling off.

I'm including links to two articles that should help you identify the problem:

https://www.gardeningknowhow.com/plant-problems/disease/verticillium-wilt-treatment.htm

https://www.gardeningknowhow.com/edible/fruits/cherry/cherry-tree-diseases.htm

If this info doesn't match up with the symptoms you're seeing, I would take some samples to your local garden nursery or extension service agent for further help.