Huge bill

Got a $9000, (yes that 3 zeros) bill from verizon for one month.  Accidentally picked the wrong plan for my stepdaughter who's fiance lives in Canada.Once I realized this I contacted them immediately and explained to them I am currently on a fixed income (worker's comp) and tried to explain this to them several times when they told me the best they could do was discount $2400 and have me pay $617/mo about one -quarter of my income) for a year and shut off my phones until it was paid. Told them that I couldnt do that and needed my phone as it was the only one I had.  They ended the discussion and were very unwilling to work with me and got rude and very accusatory. Now I believe I am getting automated calls about 10-20 times a day from them, I answered once and it went into a spiel about not being a marketing call and to press 1 for my message did that and nothing happened. Now I am trying to block the harassing calls.