Update docs to manually remove vehicle (#3075)

* Update docs to manually remove vehicle

Entry added to document how to remove a vehicle from the database until a native solution is implemented.
#3074 
#2719

* Update manually_fixing_data.mdx

website/docs/maintenance/manually_fixing_data.mdx

@@ -100,3 +100,23 @@ If for some reason a drive or charge was recorded incorrectly, you can delete it
 
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+
+## Remove a vehicle from the database
+**NOTE:** Always [backup](https://docs.teslamate.org/docs/maintenance/backup_restore "backup") your data before performing any database changes.
+
+1. Connect to your TeslaMate database
+2. Identify the right car ID in the database to remove
+```
+SELECT id, vin FROM cars;
+```
+3. Based upon the output, run the following command replacing `num` with the ID from the previous command. 
+```
+DELETE FROM cars WHERE id = num;
+DELETE FROM car_settings WHERE id = num;
+DELETE FROM charging_processes WHERE car_id = num;
+DELETE from charges WHERE charging_process_id in (select id from charging_processes where car_id = num);
+DELETE FROM drives WHERE car_id = num;
+DELETE FROM positions WHERE car_id = num;
+DELETE FROM states WHERE car_id = num;
+DELETE FROM updates WHERE car_id = num;
+```