Why does Indesign automatically change my CMYK document to RGB

I had an image that I image traced in illustrator because it was not of good quality. It was a simple black and white image with no other colors. When I image traced it i tried everything to change the black color to 60-40-40-100 but it would not keep that color selection I wanted. I checked my color mode and it was in RGB so i changed it to CMYK, saved my image tace as an eps and imported it into Indesign. I checked the color mode of the eps and when i imported it, it got changed back to RGB but the rest of my document that I originally made in indesign stayed CMYK. I double checked an made sure both my illustrator and indesign was in CMYK (which they were), but for some reason my indesign (and possibly my illustrator) keep getting changed back to RGB. I have no idea what is going on and I have never encountered this issue before. Hopefully someone can help!