Phones always go down with some problem and take forever to fix and it is supposed to be urgent as it is a business line

Our telephone lines for our business has been down and when you call or follow up you get no service and answers as to when it will be fixed. they promise clients that if it is a business it should be fixed within 4 days however that usually turns into weeks as we always have the same problem. they are the worst service provider if you are running a business and the staff, call centre agents and their online chat assistants are rude and never helpful . I even just get cut off from the online chat cause i ask when it will be fixed and if a manager can call me.