Assignments are not shown as Checked Out to other InCopy users

I need to figure out if this is a workflow issue or if InCopy/Adobe is messing this up for my team and me. 

Workflow:

My team and I have a corporate Adobe account and work off of Adobe CC. I have a shared folder with them on CC that contains the files. I create an InDesign document and create InCopy assignments. My editors open the single .ICMA file in InCopy - two different editors, two different computers, two different adobe accounts. 

However, when Editor A checks-out an assignment in InCopy, Editor B does not see this assignment as being checked out. I've watched on their screens and it never shows that an assignment is being worked on. It is only when Editor A checks the assignment back in that Editor B will then see an "out of date" notification. 

This happens for both users - neither see each other's checked-out assignments at any point, and often they accidentally edit the same assignment at the same time, and cause lots of conflicting assignment files. 

I used to work in publications with 10+ editors and never had this issue. The workflow seems correct to me, and I do not know what could be causing this "lag" in InCopy letting them know the assignment is checked out. 

Any help is appreciated.