Hi
I had a client who paid me a deposit for a cake. After paying the 50% deposit she changed a part of the design and that cost her a little bit more. When she made the final payment, it was equal to the deposit which means she did not take the extra charge into account. I know this is an innocent mistake on her part but I don't know how to tell her about it. I want to send her an email stating that I have received the balance but also that it was not the full amount but I am having a hard time wording this.
Please help if you can.
How about something like this
Dear .....
Thank you for your two payments of $x and $x on our contract #.... for your ....cake to be picked up/delivered on ......
Original price of cake was $xx and after your design changes on ..... the new total became $xxx. After applying the two payments you have a balance of $x and it is now due.
Thanks in advance for your prompt attention to this small matter. I'm looking forward to creating your cake for you.
Sincerely,
or something like that, polite but gets the point across. Like you said it's an honest mistake. Don't sweat it, just get it over with. 
Quote by @%username% on %date%
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