For collisions to work, both objects, in this case your collision component and at least one component in your character need to have collision enabled, both need to have Generate Overlap Events enabled, and their collisions need to be compatible. For example, if your collision to detect the range is let’s say of type World Dynamic, then your character needs to have at least one component with collision that is set to Overlap with World Dynamic.
You can read more about collisions here: Collision Overview | Unreal Engine Documentation