Telkom Router and WiFi Poor Response

Telkom ADSL package promised free booster but they have not delivered it despite promises over a month ago. We cannot receive signal in some rooms in our small house and the signal strength goes up and down. Our Telkom office in Swellendam has closed down and the only response we have from Openserve isthat it is a Telkom Router problem. We are very dissapointed and cannot get any help from Telkom Internet