Need more info lol. Were you consuming too much sodium or potassium maybe magnesium? I’ve been 160 hours into a fast and had a normal stool actually usually around 90-120 is when I find whatever I’ve had prior to fasting is passed normally so you shouldn’t worry. If you feel good keep up hydration and you aren’t passing blood it could be a huge number of things to pin point from over the internet.
I’m not sure, but I had a mostly normal bowel movement at day 4 before. I’m guessing what was in there finally made it’s way out. I wasn’t too concerned about it, but totally unsure why it took so long.