Afterpay Unrecognized Charge Blocking My Account

I noticed a charge on my account that I didn't recognize, they won't let me use my account until I pay it. This is really annoying because I've always been on time with my payments. I have never been late or missed a payment, so I don't know why this charge showed up. had a problem with my email a while ago, and now I'm afraid it might have something to do with this problem. When I called customer service, the person I spoke to said that they see some strange activity on my account. I know this isn't possible from my end, though. This problem has nothing to do with anything I've done outside of the norm. can't get into my account until this mysterious charge is cleared up. I've tried to explain the problem to customer service, but they haven't come up with a good solution. Need a quick fix.