Thank you for reaching out to the Community. I hope you're doing great.
There are several factors that can cause incorrect beginning balance. Check out the pointers I've listed below:
The beginning balance was incorrectly entered from the start.
A transaction older than the beginning balance was added.
Someone edited, deleted, moved, or unreconciled an already reconciled transaction.
A particular transaction was manually reconciled
To rule this out, you can open your bank register and compare the opening balance and transactions with your real-life account. Here's how:
On the left menu, go to Accounting, and then Chart of Accounts.
Open the bank register, and then locate the opening balance.
Compare the beginning balance to your bank statement.
If the transaction is match review it side by side of your bank register and the real-life bank transaction account to check if there is an issue. It does not match. Here's how to edit:
On the left menu, go to Accounting, and then Chart of Accounts.
Next to the account, you're trying to reconcile, click View Register.
Use the Funnel (Filter) icon at the top of your register and select the following:
Reconcile Status - Reconciled
If the didn't match, you'll need to correct it by clicking theEditbutton. Otherwise, you'll have to review and compare each transaction to ensure that it matches your bank statements.
I've also added some articles that will help you reconcile your accounts and keep your books accurate: