QB Issue Resolution:
I think the receive payment option solves it all.
Resolution for Issue 'How to add invoice for already received payment?' available: Yes (Solved).
Source: Intuit Community forum.
How to add invoice for already received payment?: this 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 issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for add invoice
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Error Recovery for add invoice [Canada]
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