Can I correct entering the wrong amount in posting

Hi there, mouermichael1.

Thank you for visiting the QuickBooks Community. Let me share some details on how deposit works in QuickBooks. Then, to ensure you can update the customer's payment.

If the amount you're editing is still in the Undeposited funds and you're trying to edit the cost on the Bank deposit page, this isn't currently possible in QuickBooks Online. You'll have to open the payment and change the amount to the correct one.

Here's how:

1. Click the Sales menu on the left panel.
2. Go to the Customers tab.
3. Locate the customer and click it to select the Transaction List section.
4. Find the payment and double click it to view the Receive Payment page.
5. Enter the correct amount in the Amount received box.
6. Click Save and close.

However, if the amount has been deposited to a specific account, I recommend deleting the deposit on the Bank register page. Please follow the steps below.

1. Go to the Gear icon ⚙ and select Chart of accounts.
2. Find the account you want to review. Then, in the Action column, select View register.
3. Select the Filter icon and select the filters you want to apply. Then, choose Apply.
4. Locate the deposit and click it to expand the page and click the Delete button.

Once done, you can now go to the Receive payment page. Then, follow the instruction shared above on how to edit the amount on the Receive payment page and the deposit again.

Lastly, you may refer to this article to see steps on how to reconcile your accounts so they always match your bank and credit card statements: Reconcile an account in QuickBooks Online.

Drop me a comment below if you have any other questions. I'll be more than happy to help. Wishing you a good one.