Credit Card Harassment issue

Credit Card Harassment issue: Actually My father had a credit card some 10 years ago. He was using it for a while and he will pay the bills on time.Once he spent some 10000 rupees using it and was not given any bill even after mailing the authorities. Since we didn't get any form of intimation for years, we had almost forgotten this matter. All of a sudden, we are getting some anonymous calls to our landline no and mobile no....my father has also got threats from them. can anyone tell me how to deal with this credit card company? do they have any right to collect this amt with interest even after several years or can they sue us?Other Popular Questions:https://www.lawyerchennai.com/legal-consultation/caste-certificate/https://www.lawyerchennai.com/legal-consultation/mental-harassment-by-wife-and-her-parents/