Let me help you with reconciling your account, @Anna j.  

I'm here to help you find out what's preventing those transactions from showing up on the reconciliation page. 

Reconciled transactions don't show up on the reconciliation screen. Let's check to see if these invoice payments are already reconciled by going to your bank register.

Find the categorized payments on the bank register (the account you're attempting to reconcile). Check the "checkmark" column to determine if they have the status "reconciled" (R). If so, the payments have already been reconciled. 

The reconciliation status should be reversed because they shouldn't be reconciled for the current period in that instance. Just click on the R to turn it to C (cleared from the Banking page but not yet reconciled), then choose payment. Although leaving it blank also works in your situation, status C is advised.

Another reason is that payments are in the wrong bank account. Make sure to use the correct bank account for the payments. 

In case you need to correct the balances when reconciling your account, this article will guide you through the process: Fix issues at the end of a reconciliation in QuickBooks Online.

I'm sure you'll also need to review and check your profit or expenses from your entries. If you need a guide in pulling up reports, you can read this article: Run reports in QuickBooks Online.

Any additional inquiries you may have regarding the reconciliation process are more than welcome. Do you require assistance entering your transactions and other information? Or would you like help with your reports? If you let me know, I'll get one or two guides.