Unable to load assembly group.

Can anyone help please?

Thanks vaikesh for your time.  I had referred to this article.  If you configure the service with spadmin account and try to reset manually to run the service at services.msc with spfarm admin account it runs for time being.  once you restart the services at central admin, account get roll back to spadmin.  hence configured to run with spfarm admin account, after that continuously this error coming.  please do let me know if there are any other possibilities.