extremely disgusted with procastination of the service provider

In 2017 December I booked for installation to be done in the vereeniging it was confirmed that the maximum days it can take for installation it is 4 days but to date no installation has Been done whenever I call the installers they postpone n say they have a lot of installations to it is really annoying because it is almost a month now I've been callling every day the service is worst I can't even imagine having to deal with them if possible get other service provider to do it because they clearly can't do their jobs