NSM SaaS version 2.6 onwards, NSM can automatically synchronize configuration modifications performed on the firewall from the local UI. This capability is turned off by default but can be enabled at the tenant level.
Steps to enable Auto Synchronize option for firewalls in NSM.
Login to cloud.sonicwall.com and under Manager View->Tenants-> We see a toggle called "Auto Synchronize local changes"
Enable it here.
NOTE: This setting is tenant specific, so if you have multiple tenants, you can either enable it for all or choose it for specific tenants.