Several things you need to check...
1. Is the master device actually sending clock?
2. If so, is it sending clock to the correct port? (Midi or USB depending on how the OB is connected)
You may have multiple midi ports in your system. Ensure you have selected the correct one to send clock to the OB.
3. Is the OB set up correctly? (Global OB settings need to agree with the master device settings)
Check the global settings "Midi Clock" and "Clock Port" for a start.
Good luck.