I am not using this tool correctly. Only want to cut a small 1/2 pvc pip
It only cut a part of the tubing. Don't tell me I have to rotate it or something?

Yes, but you don't need it if you have a hand hacksaw or power sawzall or miter saw. Even a serrated bread knife will cut 1/2" PVC. Clean the burrs off.

Thin small PVC will distort by compressing the pipe. Once you get the cut started you can rotate the cutter and itwill go right through.

Rotating will ease the cuting.
If it doesn't cut all the way through, tighten the screw it pivots on.
You can also apply pressure on the blade to squeeze them closed while racheting to keep the blade from moving with the pipe.

Thanks I did cut it by rotating and keeping pressure on it.

I would rotate it a little to start, then finish with pressure and no rotation to keep the end square.

Very Good. Yes it does work like that