If there are fields on the Staff object which have duplicate Name, you will experience Errors and an inability to run First Time Setup. You will first need to change the API Name of the duplicated Field.
Navigate to Setup
Go to the Objects menu and select the Staff Object
Locate the Duplicated field and change the API Name to include additional characters, meaning the field API names will no longer be the same:
Next, you'll need to remove the Duplicated Field from the Object List Query in Custom Settings.
Navigate to the Custom Settings menu
Locate the Object Field List and click Manage
Filter the List to show only the queries that begin with "i" and locate the i360 Staff queries.
You will need to open the most recent Staff query records and remove the duplicated field from every Staff query. We recommend starting with the newest one the system has created.
Click Edit:
Remove the duplicated field from the Fields in the query.
Then, you'll be able to run First Time Setup
After running First Time Setup, the new Query will show the corrected API Name of the field and the Error will be resolved.
Note: If the Duplicate Field Name cannot be changed due to the Field being part of an Apex Trigger (see screenshot below), you will still REMOVE the Field Name from the Object List Query record, but do NOT run First Time Setup. Running First Time Setup will put the Field API Name back in the Object List query and the error will persist if the duplicate field is being referenced within the Object List fields.