Boring question alert - sorry.
A regular client accidentally overpaid me on last month's invoice (they swapped two figures over). I have agreed with them that they will deduct the over payment amount from my next invoice - but they have asked me for a credit note and I have no idea what this needs to look like?!
Do I just use my invoice template (I just use a word doc), stick a minus symbol next to the figure and explain the reason where I would normally describe the services provided?
Google search for template proved unhelpful...
Thank you!