Knee doesn't bend when moving the legs IK

[Shidokami]

So I'm using the V5 version on Blender 3.0 and when I tried to move the legs bone the knee won't bend how do I fix this? tried to find someone with same issue but I can't find anyone with the same issue.

[JJJHH4466]

I also encountered the same problem.

My solution is:
Open "1" in the box "bone collections".

Select the bones of the thigh. Move a little bit in front of your knees.

Now the controller can work normally.

[Shidokami]

I also encountered the same problem.

My solution is: Open "1" in the box "bone collections".

Select the bones of the thigh. Move a little bit in front of your knees.

Now the controller can work normally.

Thank you very much it worked, 1 more question, now some of my character model cannot bend their elbow like in the picture below, should I use the same method to fix the elbow one?