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Make sure that your from-field and to-field are of the same type.
Supported types:
From standard custom fields and system fields (duedate, fixVersion, components,
Text → Encrypted Text Field or Unencrypted Text Field
Date → Encrypted Date Field or Unencrypted Date Field
Number → Encrypted Number Field or Unencrypted Number Field
User Picker (Single and Multiple)
Select List (Single & Multiple) → Protected Collection Field
Checkboxes → Protected Collection Field
Radio Buttons → Protected Collection Field
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