Two color printing

Neptune 4 I have been attempting to print with two different color, filaments I have watched a lot of videos and the process Seems fairly simple. I generally use Cura but I’ve also tried Persa And orca nothing seems to be working. All it does is just finish the test model and never pauses for filament change. In Cura I have tried post processing scripts pause at height and also filament change
Any suggestions please help