Blocking updates to a field allows you to write to the field once and then retain the original value for the lifetime of the field. This can be useful for a field like Person Source.
Admin Permissions Required
1. Go to Admin and click Field Management.
2. Find the field, select it, then under Field Actions, click Block Field Updates.
3. Select the Input Sources you want to block and click Apply.
Nice! Now you know how to block updates to a field!