Probably a SUM formula for order no. to get the total amount of order

Hi guys!

My current conundrum might sound pathetic but I can't get to grips with it. It's quite a laborious task if you don't happen to know the magical formula. Yes, you've guessed right - I don't

Here we go. I've attached a file with 3 columns; A, B, C, in which B isn't important at all. However, what is important is column A (order no.) and C (price). Now, what I need is the total amount of each order no. in column D. You'll see that I've done the first two orders manually (e.g. D3=C2+C3). The Conditional Formatting "Duplicates" doesn't work neither because sometimes you have more than 2 items bought.

Any help would be greatly appreciated as per usual!

If you have any questions regarding the file, don't hesitate to ask me!


Thank you!

Konnie