Unable to add Unit to GMS 9.x with error "Error adding Unit to Database"

While adding an unit to GMS on GMS 9.x ,  we see unable to add and throws error as "Error adding Unit to Database"

This is caused due to complexity of the password on the firewall for management of the firewall from GMS.

Change the password to more simple password to make it work and try to add the unit again to GMS