Thanks for getting back with the Community, CSBRestoration.

To rule out the possibility of a problem with your bank feed, I'd recommend disconnecting and reconnecting the account.

Here's how:
 

1. In your left navigation bar, go to Bookkeeping, Transactions, then Banking.
2. Click an account's tile to select it.
3. Use the Pencil (✎) icon and hit Edit account info.
4. Tick your Disconnect this account on save checkbox. If you don't see this option, it means QuickBooks is currently downloading new transactions. It will appear once the update finishes.
5. Select Save and Close.

Also, after undoing a matched transaction, you can match it again from your For review screen:
 

I've additionally included a detailed resource about matching transactions which may come in handy moving forward: Categorize online bank transactions

I'll be here to help if there's any additional questions. Have an awesome Friday!