*** customer service from afrihost

We are on a 75mbps up and download speed line never getting our full line speed our internet is lagging with only 1 device connected. Then when speaking to one of their agents i get told i need to run my own speed test using a lan cable i dont have a device to do this, and if i dont do this then they cant resolve this issue and im paying for this service and not getting which goes againts my consumer rights.