when I list with postage, why does my listing show up with "free post"?

[lozzagreat]

I have just sold 2 lots of greeting cards for babies. They both had postage of $5.50. I did give her combined postage.
But now she says why is there postage when It says free postage. When I look into the listing it says postage of $5.50 But not in My Ebay-  it says postage free. But it wasn't free. This is a major ebay problem. I have contacted ebay, but I don't know how this happened. I have never listed postage free for things that I can post. What else can I do?

[daniellebradydesigns]

What I am getting from this post, is that after the buyer bought the item that it says "Free postage" on the listing in 'My eBay.' 
And that it also says Free Postage on the sellers end in 'My eBay.' The buyer is asking why it's been changed to free post when she had to pay for postage?? The buyer has paid for her purchase yes??

Correct me if I'm wrong though.

Quite often when combining postage, the listing in 'My eBay' shows free postage for some reason. Also a glitch on the phone app.
Just one of eBays numerous problems.