XXXX sent me to collections immediately after I cancelled my service, I returned their Booster equipment and received credit, paid the remaining {$500.00}, via payments on my credit card. Since then, i 've been contacted by XXXX different collection agencies. XXXX telling me I owe over {$1800.00} to the last XXXX stating I owe over {$800.00}. I have been getting calls as early as XXXX and as late as XXXX, 7 days a week and they have started contacting my employer. I am now on a written warning regarding this issue. When I call I get threatened, obscenities and being told " too stupid to pay my bils ''. I left a final message with them demanding a formal notification of the debt, with proof from XXXX that it has not been paid. I NEED the calls to stop, it has begun to cause my migraines to increase limiting the days i am able to work. 
When I spoke to XXXX on XXXX, I was told they have no record of my debt owed ... so I have no idea what to do. I know I paid off XXXX., they are attacking my credit, my home and now my work.