why must i be forced to downgrade my line speed just for it to be stable

I recently had Openserve here twice because my internet was dropping constantly and was dropping when making/receiving calls on the landline .im on a 20 meg line and was receiving 19-20mbps for the past 4/5 months now this month im dropping constantly and receiving heavy packet loss ..sometimes im sitting around 20 000 packets dropped even though the agent has replaced my jacks and line to where it connects outside from then pole and said my speed would be fine and wouldn't drop and pinned it at 12mbps .Openserve wont hear anything ..i just get told only solution is to downgrade.Im paying for a service that im not receiving .I cant even upgrade to Fibre because the agent said it wont be in my neighborhood for another year .This is Ridiculous ,their has to be a solution .i use the internet for my business and i have to use my cellphone every time because the landline causes the internet to drop.Deeply disappointed in Telkom/Openserves way of dealing with things.