PLEASE HELP TO GET RID OF THEM

Too long a story but have been fighting with them sincee October. I gave notice of their services plus returned their Router. I have been constantly sent emails to return Router. I then got money deducted from my account without my authorisation R1524.28. Have been on to their whatsap app since 1st November to try to fix this. In one week I have spoken to 9 different agents who have all promised to fix for me. I have now gone into my bank who has issued a stop payment on my account and also to try and get my money back. They are so unresponsive and you cannot speak to anyone in charge. Im fed up trying and just waiting to see if they take more money off my accoumt. Please can you help. I just want to get rid of them and let the people outside to know. Thank you Helen