Why not split the Excel File in to pieces & do multiple imports rather than just one big one.

Resolution for 'Adjustments memos issue: 'Pos huge Adjustments memos can not be sent to quickbooks' available: Yes.

The Adjustments memos 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 Adjustments memos issue yourself by looking for a resolution described in the article. If it is a complex Adjustments memos issue or you are unable to solve the issue, you may contact us by clicking here or by using other Adjustments memos support options.

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