Hello
Thank you for contacting BitPay support.
Your issue is related to a temporary synchronization offset we are experiencing and should not take long, Your funds are safe.
Our team is currently working on it, we will reach out back to you shortly.
This happened to me once with Copay, which the Bitpay wallet is based on. If the problem is on your side, there's a way to sync the wallet with their servers. If you navigate through the gear icon > wallet settings > transaction history, clearing the cache will do it.
If that doesn't work, the problem is on their side. You can always import your keys into another wallet if that happens. I'd recommend against Bitpay or Copay anyway, as there are much better lightweight wallets out there.