Bad customer service

Im being handed over to the debt collectors, on the 16 September i received notification about balance of R908 and on the 05 October i paid R300.00 and the recent balance is R983 according to their records now when i request a statement im being told that im not the account holder as i given them a wrong cell phone number and wrong email. So im not sure that i still owe them cause according to my understanding im finished paying on February with the last payment of R400 can you please assist me to check if im not being wrongfully charged with someone else account thanks in advance for the help. Mosima Dikgale ***