Make up the difference: it means that the things you bought were made up after you didn't pay the money you should have paid, or that the postage on the things you bought was a few dollars less.

For example:

1, one thing was built by 36 yuan, but the only thing you bought was 35 yuan. If you want to build it, you need to add 1 yuan.

2. There is another one. For a friend's birthday or something else, you buy a cute doll from 76 yuan for your friend. If you want to write a blessing on the doll, the seller won't write it for free. You have to make up the difference and write what you want to say on it.

Extended data:

Refund price difference refers to the difference between the new accounts payable and the original accounts payable due to the change of commodity unit price in actual settlement after the enterprise purchases goods from suppliers in normal business activities.

References:

Refund the difference-Baidu Encyclopedia