u/Embarrassed_Code4064

I am wiring in jdm indicator stalk but jdm indicator stalk dosent have rear fog light so I tried to wire in a seoperate switch for the rear fog light (signal wire to indicaror switch blue with red line) with the signal wire for the rear fog light but when I turn it on at the same time as front fog light or something else it turns off why. Is it something to do with the BCM everything works as it should when the car is turned off. How do I wire in the rear foglight signal wire should I just put in my own relay wire it myself or something or is there someway to do it