Hip bone must have children?

Hey guys,

I’m new on this forum and I’m new with Blender, though I’ve figured out a lot already due to online tutorials.
I’ve recently created a human mesh with the help of Makehuman and everything was working fine until I tried to load and retarget on of the bvh files i downloaded on to my human mesh. I’ve done it before (though with different bvh files) and I’ve never come across any big problems.
As soon as I upload the bvh file, an error message comes up saying:

Category: Identify Source Rig
Hip bone must have children: r_subtalar

I have absolutely no idea how to identify a source rig and I don’t know what r_subtalar means.
Does anyone have any idea how to solve this problem?

Thanks in advance!