We have FDI version 3.8.0 ready to download. Series 3.7 were quite shaky as we moved away from EL7 Ruby (2.0) to RHSCL Ruby 2.5 and then 2.7. Latest build was not working correctly, which is now all fixed.
https://downloads.theforeman.org/discovery/releases/3.8/
Report issues on our tracker. Thanks