Measure CoreXY Belt Tension

Dear community, I'm trying to get my COREXY tension graphs for an IDEX system. Under the calibration TAB when I select MEASURE COREXY BELT TENSION, I can only select Toolhead 0 and not 1. So I am only getting the graphs for my left belt. In the comissioning guide it tells me I should select MEASURE COREXY in the scripts section but this is not showing in my Mainsail. Can anybody please give me some guidance?