Sorting layer in with override canvas component

hello,
I have intractable system of drag and drop using UI item.
The UI item have Ui EventSystem write on it in code, that allow me to drag it and drop this item.

I wanted to have the picked element to be on top of all other by using Canvas component over it and use override sorting in code while OnPointerDown.

The problem:
When i add the canvas component it stops all the interaction with the UI element, none of the EventSystem Methods are working. no matter what layer \ sorting number i give them.

is this a known problem ? is there a solution ?

Have you added a GraphicsRaycaster to the canvas object?