I had a problem with the sony book store a few months ago.
I'm in the UK. So I emailed support with my problem (I had a bunch of books in my cart but no BUY button) before I went to bed.
I had a response from them next morning seeking clarification, problem was solved that night.
Couldn't fault them.
I've now spent about $250 on books from the Sony Store (including my free $50) - yes the interface is a tad clunky, but honestly, I can find the books I'm after, I've swapped PCs, re-installed PCs, authorized and de-authorised (one time with support help, again via email, as I'd re-installed a PC without de-authorzing it first
) and re-downloaded them all a few times and as far as I'm concerend the Sony Ebook Store / Connect / library whatever it's called pretty much does what's it's supposed to.
So, getting back to the original post - I'd email support telling them exactly what's happening - they may come back and ask if they can login to your account (they did for me) and I'm sure they'll sort it.