Im getting paid twice every month by my company. What should i do?

I work for an indian mnc. My mnc has 8-9 companies under it. I was working for one of their startup. In December, i was shifted to their new startup. I was getting my normal salary till November. From December onwards i started receiving salary from their old as well as new startup. I got it once so i didn’t speak about it. I got it another time today. What should i do?

Edit: joined the company 7 months back as a fresher. The new company is just for the name sake, as there is a limit to number of traders a registered company can have. My salary portal shoes just one time payment. Also im getting paid from 2 different bank accounts.