Since version 8.1.1 duplicate QER-K-ShoppingRackCheckDecision and QER-K-ShoppingRackMakeDecisionEX DBQueue tasks may occur.
This can lead to a double execution of the 'EX' process chains behind it, with unwanted side effects.
This is a product defect (32898).
This will be fixed on a future release of the product. If you require this immediately corrected, please contact Support for a hotfix referencing the defect ID 32898.