Weird issue with THC

I have an issue that came up recently with the cut beginning, running through about 25 seconds of cutting, then the torch slowly begins raising off the material. I have a solid ground clamp on the material and new consumables. I have had this begin happening on almost every cut on the same cut design or different ones. When it happens I turn of THC and run those cuts again. It is becoming quite annoying.

Any ideas?

Thanks in advance