Really bad service

Really bad service. My car went for a service(11/06/2018),they phoned me and told me that they need approval and to order a part. They got the approval and told me that they ordered the part and my car will be ready on 13/06/2018. My car was not finished and they told me they had computer problems and the will order the part and my car will be ready today(17/06/2018). When I phoned them they told me that they did not order the part and that they will order the part. They told me that they do not have any courtesy cars that I can use and can't help me.