QB Issue Resolution:

Choose the Gear, then Company Settings, then Advanced, then Miscellaneous, click the stupid pencil, and then finally change the Date Format.

Resolution for Issue 'How do I change the date format in the quickbooks online version?' available: Yes (Solved).
Source: Intuit Community forum.

How do I change the date format in the quickbooks online version?: 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 Company Settings
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