QB Issue Resolution:
Create a new checking account, then rename your old checking account to be the same name. This will prompt you to merge the two. I’m not sure what that gains you though.
Resolution for Issue 'How do I merge accounts and their costs with a new checking account?' available: Yes (Solved).
Source: Intuit Community forum.
How do I merge accounts and their costs with a new checking account?: 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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