5 months with no solution

Please assist - we have tenants staying in our building and have been attempting for the whole of 2015 to get the ADSL (which we are paying for) functioning for them. Fourth time this year we are reporting a fault - The first two callouts simply said there is nothing wrong (with no option of following up, they just close-out the fault, and we have to pay, even for the one time they only notified on the Friday afternoon that they will be there by the Friday afternoon and there was no-one available to open for them), third callout said the modem/router was faulty. A new modem was suggested, which was bought from a Telkom outlet store and delivered to the tenants. The router still shows 'no internet connection'. I have tried to set it up according to instructions on the Telkom website, but the login page (step one of the process) cannot be accessed because there is 'no internet connection'. This is extremely frustrating! If someone can please simply explain to me what the problem is and how to correct this then we don't need to go through the useless 'online fault report system' again...