No you should not be selling to yourself
I do not use POS so you will have to find and use inventory adjust and select the adjustment account for demo expense or shop use expense, what ever you have set up and lower the qty on hand
The value of the adjustment […]
Resolution for 'adjustment account issue: 'How do I account for internal use of an inventory item?' available: Yes.
The adjustment account 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 adjustment account issue yourself by looking for a resolution described in the article. If it is a complex adjustment account issue or you are unable to solve the issue, you may contact us by clicking here or by using other adjustment account support options.
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