Wait 10 seconds, and then plug the console back in.Hold down the PlayStation Power Button until you hear two beeps.Wait a moment and plug the cable back in.After the console is completely turned off, pull out the power cable.Press and hold the Xbox Power Button for 10 seconds.Have you tried turning it off and on again? Power cycle your PC, PlayStation, or Xbox.Close and reopen Call of Duty: Vanguard.You can find a series of troubleshooting steps beneath, we found success on several occasions with these simple fixes:
How To Fix CoD Vanguard's Error Code Kadena - Keesler?