There is an annoying problem with ATC console window. Randomly, time to time after ATC instruction received, the response options disappear, there is no way to acknowledge the given instruction and my flight plan is cancelled automatically (after few confirmation repeats from the ATC). To solve that, I have to load my flight plan again which is disgusting. The behavior is following - in the middle of the IFR flight, at some random point, ATC gives next instruction, however the are no response options, the ATC window is empty, so I can't give a confirmation. The ATC is asking to acknowledge few times and than cancels the IFR flight plan. Immediately after canceling the IFR flight plan, the ATC window becomes fully functional again. Anyone else faced the similar issue? How to investigate and fix that?