'ax_addvehicleform' at function a!buttonWidget [line 150]: An error occurred while executing a save: Could not cast from User to Date. Details: CastInvalid

a!buttonWidget(
          label: "Add Vehicle",
          saveInto: {
            a!save(ri!vehicle['recordType!{691ee044-4a47-4798-bd87-7f96ca362496}AX Vehicle.fields.{b54f728c-5e71-4d1f-aad7-661d05c22098}vehicleDateAdded'],
            today()
            ),
            a!save(ri!vehicle['recordType!{691ee044-4a47-4798-bd87-7f96ca362496}AX Vehicle.fields.{b54f728c-5e71-4d1f-aad7-661d05c22098}vehicleDateAdded'],
            loggedInUser()
            )
          },
          submit: true,
          style: "PRIMARY",
          validate: true
        )

I'm working on process models & trying to debug the add vehicle form for adding a new vehicle but after entering the details & I select add vehicle button, I'm getting the above error. What should I do in this case ?