Call centre dropping calls on ***

Billing and collections is droping calls. I called 10 times from different numbers, goes through I hear someone typing call then gets disconnected. Purposefully i might add, heard talking in background. I called from *** and *** if you need to track down the agents... Check case number: ***, please just refund the overcharged amount I explained it all in simple email text to a agent replying to me who is not so clever, or is just lazy and does not want to check properly into the matter. Please someone assist the people that work there they are dragging your company down....