Hi everyone, I'm not able to delete this DLO or its mapping. It keeps saying it's a primary key. I've already deleted the segment and anything linked to it, but the DMO still shows a relationship that appears non-editable. Has anyone run into this

Thank you for your detailed answers, guys! 

Actually, I had just added a stream and DMO mapping, then tried Identity Resolution only. I deleted that after testing, and nothing else was left. I checked each and every tab, nothing was there. It just wouldn't let me delete that relation. 

After trying multiple ways, I found an option in the data model to edit the category. I switched it to "Other," and after that I was able to delete it since the primary key logic became invalid. It looks like a technical glitch, nothing was actually connected. 

Thanks again for your help!