My "create custom field" button isnt there

My "create custom field" button isnt there

In Zoho CRM I went into setup and tried to create new fields, but the button to create a new field is missing.  I know this is not due to me having already created too many fields because 1) I havent created that many and 2) it would just alert me that i'd already created too many custom fields for the free version and I would have to upgrade in order to create any additional fields.  does anyone know where my button went or why it is missing?!