Harrassed by calls from online website

Hi I have created my account on an online marketplace that gives consumers access to apply for credit card. I have submitted my details to them on 7 Dec and have filled one application on 7th but have saved it as draft and have not submit it. After inquiring from friends and family who have already used that site i decided not to go forward for credit card and applied directly at bank. I got my card few days before from bank. I have send website customer care to delete my account on 9th Dec from their website and remove my details. From last 20 days i have been mentally harassed by this website customer care. just today after being tired of calls and i have switched off my mobile for one complete day. in the evening when i switch on i received a msg and mail from that site that they have submitted my application and is in review. I want to file a consumer case of defamation and mental harassment. please advice correct IPC for this. i didnt understand even after saying no for my credit card application for 10 days why have they submit my application. please help me on this.