- "Date in format of YYYY-MM-DD HH - MM - SS required for field"

Explanation and resolution:

This error can be returned when you try to edit an item through the UI and if you have an existing custom field, which was created as a Date type. Please bear in mind, that unlike the other variable types of custom fields like Varchar, Int, Text or Longtext, the Date type would require a valid date in the above format and in order to avoid and bypass it, you would need to double check and make sure the date you are using is valid and in the accepted format.