The network that 😡 you none stop

Hello this is Deyola Steyn here. I am experiencing between 2.5 and 7.5 mbps download speed but I've signed up for a 20mbps line. Most the time the network is dwindling around 3mbps which is a headache because online movies keeps on buffering. I do hope they can sort out the issue or else I'm migrating to another ISP.