I’m not sure what no’s means, but from what you say you are selling more than you stock, so naturally the qty on hand will go negative

QB does not stop you from selling what you do not have, there is no setting to control that.

If you are buying the item […]

Resolution for 'breakdown function issue: 'Sales Regarding items' available: Yes.

The breakdown function 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 breakdown function issue yourself by looking for a resolution described in the article. If it is a complex breakdown function issue or you are unable to solve the issue, you may contact us by clicking here or by using other breakdown function support options.

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