Calendar Visual to highlight days with total logs exceeding specific value

Good morning

I have data tables with logs from our service desk. The team receives various calls regarding issues with a number of systems. I would like to build a calendar (either Annual or Monthly with time Slicer) which will display a visual calendar and on the days where the number of calls exceeds X calls, the day will be marked with the system name (or names if more than one meets the criteria (and possibly a color gradient - but not essential). 

I have tried the Calendar (by Datanau) however that is only giving me the total calls per day. It does not allow me to list the system name according to total number of calls per system.

Really grateful if someone can assist me 🙂 Thanks