The Accounts Receivable Aging Summary report shows the unpaid invoices that are already overdue. If you want to see the details of every summary, you can pull up the Accounts Receivable Aging Detail report instead. You'll know more about it through this link: Run an accounts receivable ageing report.
Meanwhile, you can pull up the Sales by Customer Summary or Sales by Customer Detail report. These reports will show you the income for every customer in a monthly or yearly basis. You just need to set the correct Date range and Accounting method.
Click Reports on the left menu and search Sales by Customer Summary or Sales by Customer Detail.
Set the correct Report period and Accounting method (Cash or Accrual).