QB Issue Resolution:
The reconcile date fields (and several other fields) require US formatted dates of the form MM/DD/YY. You are using DD/MM/YY. This is controlled by your Apple System Preferences under Languages and Region. Click on Advanced and set the short format to MM/DD/YY as in the attached picture. Then it will work.
Resolution for Issue 'Bank Reconciliation will not accept date – invalid' available: Yes (Solved).
Source: Intuit Community forum.
Bank Reconciliation will not accept date – invalid: 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 Quickbooks
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