Team Project - Video Media Suddenly Offline

I've been working with Team Projects for about two months now. Today all of the video media suddenly went offline. Nothing has changed on my computer that would explain this. I'm still using the same external drive with the same files as I have been. My computer is a Mac OS 10.11.6, and I'm working with Premiere Pro CC 12.0.1.  I tried Edit>Team Project>Media Management, nothing happened when I clicked on New Media Mapping, or Edit Media Mapping. I also tried shutting down the program and relaunching, and switching my external drive to a different port on my computer. It still shows the video media offline. I'm using proxies from Red footage. I was having trouble sharing changes yesterday, and had to shut down and relaunch several times, but other than that I can't figure out why this is happening.