Extremely disappointed

I am so disappointed in this wifi. It is definitely not what we expected. We forever buffering and our things take forever to download or open. Everytime we phone they say that we have the correct line and connection? How can I be connected with good connection when my inlaws have a 4meg line with another company and I have a 6meg but I am forever buffering and they are not. How do I report this besides through their offices here in port elizabeth