That is a known issue with the Pro and the way Hypertherm measure delays. Hypertherm starts the clock when the arc fires, Langmuir when the command is issued. Langmuir includes time for contact to close, arc to start. Here is their suggested method of finding the right value:
Was the torch firing at the time it froze? Have you removed the inductor?
If you are a little bit computer savay download OBS and capture the screen during each cut. This will allow you to replay what the THC is doing. Alternatively set your phone up to record the screen. Hopefully the new version of Firecontrol has THC logging, because it would really help diagnose situations like this.