How you delete a geogrid, and whether you can get it back, depends on what you are deleting. There are three separate things, and only one of them can be recovered.
Deleting a single live geogrid
On the Live GeoGrids index, click the three dots to open a menu that contains a trash icon to delete the geogrid. The same action can be performed when viewing a geogrid - in the upper part of the map there's also a deletion button. This is permanent: a deleted live geogrid cannot be restored.
Deleting a single geogrid inside a scheduled config
Individual runs inside a scheduled config can also be deleted. Like live geogrids, a deleted individual run is permanent and cannot be restored. If you only want to stop tracking a keyword, pause it instead (see below) rather than deleting its runs.
Deleting a scheduled config
On the Scheduled GeoGrids (configs) index, click the three dots on the right - there will be the trash icon that deletes the whole config: all of its search terms, runs and history. Unlike the two cases above, a deleted config can be recovered for a limited time.
Pausing without deleting
To stop tracking without deleting anything, open the config, click Edit, and toggle off the search terms you want to pause. Paused terms keep their history and stop consuming credits on future runs. This is the safe alternative to deleting. If you want to pause the entire config, change the schedule to "On demand".
Recovering a deleted config
Only a deleted scheduled config can be brought back, and only within 2 months of deletion. After that, LocalOptics permanently purges the config along with its runs and history, and it can no longer be recovered. Single live geogrids and single runs inside a config are never recoverable.
On the Scheduled GeoGrids index, set the State filter to Deleted.
Find the config and click Restore.
After restoring, reschedule the config. A restored config does not run again on its own until you set its frequency.