Of the check list of items to check ...
1. have you checked the data cable to the printer is fully inserted and has no damage to it?
2. Are your driver settings correct?
3. Have you tried uninstalling and installing the printer and flexi printer setup (inside the production manager)
4. does your printer have an internal diagnostic? and have you run it if it does?
5. Have you tried hard resetting the printer (while on, pull power source ... or performing a master reset internally on the printer)
6. have you tried printing from different computers?
7. Have you tried replacing the data cable?
8. Does your system show any device errors in your device manager (I'm assuming your running windows on this one)
lastly ... 9. if all those have been attempted ... have you tried uninstalling and reinstalling flexi?