QB Issue Resolution:

Balance Sheets balance; P&L’s don’t balance.

If the check was entered in error and didn’t happen, then it is incorrectly impacting your books for that period.  You can choose to fix it in place and then update any reporting for that period, or fix it in the current period. The Void feature should ask you which you want as you Void the check.

Resolution for Issue 'what is the best way to remove(cancel) a check that has been entered but will not be cashed' available: Yes (Solved).
Source: Intuit Community forum.

what is the best way to remove(cancel) a check that has been entered but will not be cashed: 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 balance sheets
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Error Recovery for balance sheets [Canada]
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