Kotak Mahindra Bank — collection agent abusing and calling continuously on office landline

Address:

Mumbai City, Maharashtra

For a partially paid loan from Citicorp Finance Ltd. which I intend to pay back. Persons from ISGBL Collection AC calling me to pay the pending amount of RS. 37000 on behalf of Kotak Bank Ltd., Santacruz Branch, Mumbai, telling that Citicorp has been taken over by Kotak Bank Ltd. While I expressed my intention to pay, I was told to transfer the money by NEFT to ISGBL Collection AC in Kotak Bank at Mumabi branch with A/C details. When requested them to give a few days time to verify the authenticity of their organization they started abusing me, calling at my office EPABX number more than 80 times in a day and irritating the office person to that extent that my employer gets irritated of me. I have already filed a complain with Mumbai Police mentioning the person and his mobile number. Am not sure if there will be any action. I stay in Dubai now. What do I do now?