Just to clarify the listings, the OP has selected the Local Pick-up only option and has not stated any postage costs. As we all know, this unfortunately displays in search results as Free Post, but when you look at the postage options, there are none stated. (Cash on delivery is a payment option, not a postage option).
The listing description I looked at stated Local pick up from Preston or happy to post at buyers expense.
I am presuming all the other items were listed the same way, and while the listing format is a little confusing, the seller isn't really the one at fault here.
OP, to fix this issue, you need to change the way you list a little. Click Add or remove options in the postage section and make sure the Local pick up option is ticked, then save. 'No postage, local pick-up only' will then be available to select in the dropdown menu. You need to use that rather than leaving a flat rate postage option, as then the listings will displaye Pick Up only, not Free Post, in search results. You also need to select Pay On Pickup as a payment option (not cash on delivery). Either do that, or state your flat rate postage costs up front and then tick the box to say pick up is also available.
In this instance, because the way the items were listed are a bit confusing, I would agree to a refund if that's what the buyer preferred. I'm not sure if you can do it before the eCheque clears, though, and that can take several days.
