Hello there, Leeanne79.
There are a few possible reasons why your balance is not showing up the correct amount after reconciling your credit account.
It could be that there are transactions that are already beyond the time period. If so, the automatically-recorded opening balance may not be the correct beginning balance. Also, this article provides the causes and troubleshooting to resolve them.
I've also provided some helpful articles about Reconciliation:
The Community team is always here if you need more help with this.