Unreliable internet

Last public holiday I had to complain because I had no service for almost a week. Following 27 April again I have terribly slow internet and intermittent connection. It's been 2 days with less than 0mbps upload and less than 4mbps download. What kind of service is this? I understand that towers need maintenance but this is unacceptable. In addition, after logging the complaint with customer service I got promises that they would call on Tuesday but no one did. All they do is ask you to unplug and plug in the router, improves for a few minutes then it's back to square one.