Cred App Dream Technology Bangalore — Fradulent transaction of 30,021 from CITI Bank credit card

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Dream technology Bangalore cred app

I have received a bill amount Rs 30021 under the name of Dreamplug Technologies on 5th Sep. However, there was no otp or information received from CITI Bank. Bank is refusing to investigate the disputed transaction and stating that this is secured transaction. How this is a secured transaction when I have not received any email message or call. Please help me get refund.