phone line not working

On the 25th August 2015 I reported my landline is not working. They told me they will send a technician to check out the line. Did not happen. I went to report the line again at their branch in Riverside Mall. I received a mail telling me the line has been reported. Last week again I went to their branch in the Mall ( they don't answer their phones). The lady how assisted me told me they don't answer their phones because they are understaffed and they don't have technicians to help and my complain is not old enough for them to help me!!!My problem is this is a business line!!! What should we do to get our phone line repaired? Everyday my line is out of order I am losing business.