Exchange 2016 DAG SwitchOver Issue

 Recently Testing in LAB for patch

Even After

Stop-DatabaseAvailabilityGroup -MailboxServer Prod1 -configurationonly

Stop-DatabaseAvailabilityGroup -MailboxServer Prod2 -configurationonly 

and then 

Restore-DatabaseAvailabilityGroup 

no error, Cluster also up but database didnt mount and cannot mount

Finally

net start clussvc /forcequorum

start-DatabaseAvailabilityGroup  -identity DAG2016 -mailboxserver DR1

最大问题是 Restore-DatabaseAvailabilityGroup 没有error msg..