Zomato — account hacked

Address:

New Delhi, Delhi, 110060

My account was used by someone else from Bangalore. My zomato account is directly connected to my Paytm account and he may order form that directly. I know today only, he use it in past also.
In past he used for 3-4 times. May be he reached to my Paytm account through Zomato so may be cut some amount from that also.
And Zomato has no customer care service center to whom we can directly resolve issues, they have robotics chat box and I have fear that if I chat from that then hacker may delete all history and all that.
I am also complaining against Paytm that they should also provide for second verification when some other app is using there app.