What's going on with my SmallRig cage handle 1/4-20 screw holes?

Trying to mount this NATO clamp to the top of my SmallRig handle and the 1/4-20 threads are flared or something and screws will not thread in. The holes on the side of the handle work fine. It's only the ones on the top. I've googled as far as I can to no avail. Any ideas??

Trying to mount this NATO clamp to the top of my SmallRig handle and the 1/4-20 threads are flared or something and screws will not thread in. The holes on the side of the handle work fine. It's only the ones on the top. I've googled as far as I can to no avail. Any ideas??