Dynamic spotlights leaks when increase outer Cone Angle

When increase spotlights outer cone angle, light will leaks on other side of wall. If use default setting with outer cone angle anything works fine.
Currently, if increase contact shadow length will slove the lights leaking problem, but it will make shadow looks artifacts.
Spotlights setting:

Dynamic light in general just tends to leak. You can tweak shadow bias and other settings but there isn’t a good way get rid of it completely.

I was hoping to use dynamic lights in a current project, both to get some experience and also cut down on baking times, and was having issues with leaking. I found a post, which I can’t see to find now, that suggested tweaking shadow bias and some other setting I forget. Helped but wasn’t enough.

So Sorry to Hear About… if thats the true