Go to gear>product list> create items for your missing courses.  This is where you will attach the income acct.

Resolution for 'create items issue: 'When invoicing I can’t select all income accounts/services/products, some do not appear on the drop-down list. How do I change this?' available: Yes.

The create items issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the create items issue yourself by looking for a resolution described in the article. If it is a complex create items issue or you are unable to solve the issue, you may contact us by clicking here or by using other create items support options.

For more information about resolving issues related to create items in Quickbooks/QBO or to get support for the issue 'When invoicing I can’t select all income accounts/services/products, some do not appear on the drop-down list. How do I change this?', click the link below: