QB Issue Resolution:
Sounds like you didn’t include the TRNSID and SPLID fields in your file. Add them in the second column and then it should work.
Resolution for Issue 'Why do I get “Can’t remove the ID from the split definition in the middle of the import file” randomly?' available: Yes (Solved).
Source: Intuit Community forum.
Why do I get “Can’t remove the ID from the split definition in the middle of the import file” randomly?: 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 Import
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