Icetomb causing enemy to become freeze immune

Hi, when using icetomb it causes freeze to build up along with my other skills. However, if icetomb is the last item/skill to apply freeze where the counter hits 100%, enemy remains unfrozen and the freeze counter disappears. You then are unable to apply freeze from any other skill on that particular enemy for the rest of the time it’s alive, white mob or boss. At first I thought cold snap was the problem or some other skill using ele focus. Now I can confidently say it is icetomb doing it. Tested without icetomb on and can use all skills and keep applying freeze reliably.