Find "Other Payment Name" and type the title of extra payment option you would like to have

Scroll further down to around 4/5th of section

find "Use Other Payment (GIFT)" and tick the box

Click "SAVE" on the top right

Move back to main page and press the refresh button

Take Payment

As normal, move to payment view.

You will find new button next to "Card" button

Click this new button.

You will have three options.

Select "ENTER" to enter amount

Enter the amount and press Done.

On the bill or receipts, this new payment option will be shown like below