This is an issue because all of our user defined fields are stored in the database as text fields so the report doesn't know to convert them.

 To fix this issue simply:

  1. Create a new calculated field
  2. In the properties window - change it’s type to date 
  3. Set the format to M/D/Y (or whatever date format you require)
  4. Create the expression of the calculated field and set it to the user defined field database field that you require to be formatted as a date.