HDFC Bank — threatening call

i have been getting threatning call from hdfc bank, iam a student and i was given card by hdfc bank now as iam not able to make the payment, they are calling at my land line number and harassing my parents and some times they say that we are calling from delhi high court and ask rishi to make the payment .i have told them many times that after six months i will get a job then i will settle the account .last time also they came to my home and told my mom to give the money otheerwise the consequence will not be good so my mom paid the money(minimum amount).now daily these people are calling on my landline and mobile number and threatning me and my parents