It is not possible to save changes to a global or group report that you did not create.
Click the arrow next to the Save button and select Insert and
Stay to save a personal copy.
If a user opens a global report and tries to save it as a group or personal report, the ServiceNow platform copies the report
rather than changing its security state. Copying the report allows users who cannot create
their own global reports to modify a global report, and then save a personal version of the
If a user opens a personal report and tries to save it as a group or global report, ServiceNow moves the report rather than
copying it. The user must have the appropriate rights to create a group or global