Dan --
That exact same thing happened to me just a few days ago.
A reseller site, Flutterwave, took my money, charged my card, and did not apply it to Depositfiles
I emailed Depositfiles along with the emailed receipt I received from the reseller. It took a few days, but I'm now back to being a gold member. It's a shame this seems to be happening to many of us with all the work we have to put in to keep our membership.