Hey @user2162​ , You should probably reach out to Intercom support through the messenger for this one. There's not enough info here for anyone to really help other than to say try refreshing your page (which you've likely already done plenty of times). If you could add a screenshot of your segment setup it might help but Intercom support would be best at assisting.

Hey @user2162​ — I had this error when I was accidentally adding "Segment 1" as a filter inside "Segment 1".

I actually wanted to add "Tag 1" as a filter to "Segment 1".

Check your segments, make sure there are people in them and that you're not trying to filter by the segment you're trying to save.