QB Issue Resolution:
Go into the Expense, Check or Bill transaction that triggered the billable expense, and click the check mark (not “View”) in the Billable column TWICE, to clear the box. Save.
To find them, go to Sales>Customers, and click the box that says UNBILLED ACTIVITY, click each customer and open the Billable Expense Charge. Then click the link on top left to the Expense, Check or Bill.
If there are many billable expenses, there is a utility to delete in batch:
Resolution for Issue 'How do I change expenses to not billable' available: Yes (Solved).
Source: Intuit Community forum.
How do I change expenses to not billable: 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 bill transaction
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Error Recovery for bill transaction [Canada]
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