Why can't I send a partial refund to my customer for the savings of a combined shipping charge...?

[lyma372]

I can find the refund area in the item's description, and I can add the amount I want to refund my customer but the 'refund' button remains greyed out, so I can't finish the refund. He paid £8.50 for the item, I only want to send him £2.88 back as he overpaid for shipping (because I combined his two purchases into one parcel and saved on the shipping charge). It's not much money - but I think a nice gesture. Can anyone help? Thank you so much. Lyn

[lyma372]

I figured it out! I had to choose a "reason for the refund" first from the drop down. mystery solved. Lyn.