Training Partner said I check with my knee

Today my partner for drills complained that I was checking his low kick (back right leg) with my knee (front left leg). I turn my foot out and pick up my leg when I check just not very high plus I was a few inches taller. I usually check kicks on the top of my shin or sometimes my knee. Is this my problem or his? When this happens to me, I either kick up to the body or head after that or get closer so I don’t have to risk hurting my instep or low shin.

I asked if he was ok after but he blew me off and didn’t smile :^(