Backup SQL database (ALways on from the active node)

Hello

we are trying to run a backup from the active node for the SQL DB, we are using BE2014

while trying to select the SQL database we are getting a prompt that we are not able to connect although we have added an account that is a sysadmin account  & that have DB creator rights..

Can you please advise what should be the specific rights? and why sysadmin account is not able to connect.

thanks

Sircon