As per regulations, MTF is only available for select exchange approved NSE equity scrips.

View the list of scrips available for MTF 
On the Neo platforms: 
1. Search for the stock, go to the stock details page and click on Buy button to evoke the order form. 
2. Select the Product Type MTF. If MTF is unavailable for that stock the Buy button will be disabled and you won’t be able to proceed further with the order placement.