SAP Message R5544 - City &1 has no different postal city, so moved to field 'City'

Diagnosis The city <(>&<)>V1<(>&<)> was entered in the field 'Diff. res. city',and the field 'City' was empty. As city <(>&<)>V1<(>&<)> does not pointto a postal city, it should not be enterd as 'Diff. res. city'. It istherefore put in the normal city field.