no fax working as told

i was moved over to telkom wireless service as telkom was moving away from the fixed lines .when the first time i to9ld them that i need a fax they said it wont work and the idea was abandoned .a year later i was called again and when told that i need the fax line to work i was tols by the sales agent that they have a modem sustem and the fax must be connected to the modem and it will work .the system was purchased ove r a 24 month contract and when ninstalled the fax does not work .when i called support told me the fax will not be compatiblke and there is nothing that can be done .now i am sitting with a useless service ,i had the land line for fax as a doctor sending prescriptions