Iwc marine chronograph does not store power

When it's activated, there's a draw on the overall power which basically leads to a reduced power reserve (the watch won't run as long as it normally would without the chronograph on - could have an effect on timing in the lower end of the torque curve of the mainspring). I recently bought it and it runs wonderfully with zero issues, however, I noticed recently that the power reserve will get down to the edge of 2-days (IE: between 2 days and 1 day marker), not even yet in the red, and the watch will stop. How much wearing movement is required to maintain the power reserve level, and it seems even with Gen the answer is “too much”. The problem that I was having is that when pausing the running chronograph and then trying to resume it, the chronograph would sometimes not start running again. A chronograph is a time keeping device that simultaneously tracks elapsed time on demand.