Thank you for reply Dirk. Finally DIO module started working. When I logged in first time I used Mac address and serial number. The Mac address was correct but the serial number I have written were numbers of first two lines next to QR code instead of second line only. This can be the reason for thi...

My DIO module stopped working after I have flashed new stretch firmware to revolution pi connect+. Anyone can please help me what I can do to fix issue?