Welcome to the community! There are two ways to use the instance_name in KoBoToolbox. You could use them as follows:
If you wish to use them during the design of your survey form, you could do them as outlined in the post (using them approach the enumerators will not have access to change the instance_name during data collection):
And, if you wish to use them during data collection (with KoBoCollect android app), you could do them as outlined in the post (using them approach the enumerators will have full access to change the instance_name during data collection):