How To Fix WB2_SE_TRO021 - Exactly-once request cannot be locked: &1 (error code &2)

WB2_SE_TRO021 - Overview

• Message type: E = Error

• Message class: WB2_SE_TRO - Message Class for Trading Order Services

• Message number: 021

• Message text: Exactly-once request cannot be locked: &1 (error code &2)

Self-Explanatory Message

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WB2_SE_TRO021 - Details

• The SAP error message WB2_SE_TRO021 indicates that a request cannot be locked because it is already being processed or is in a state that prevents it from being locked for an exactly-once processing scenario. This error typically occurs in the context of SAP's Event Management or Process Integration (PI) scenarios where exactly-once processing is crucial to ensure data integrity and consistency.
  
  Cause:
  
  Concurrent Processing: The request identified by the key (e.g., &1) is already being processed by another transaction or session. This can happen if multiple processes are trying to handle the same request simultaneously.
  Locking Mechanism: SAP uses a locking mechanism to prevent data inconsistencies. If a request is already locked by another process, any subsequent attempts to lock it will result in this error.
  Long-Running Transactions: If a transaction takes too long to complete, it may hold the lock longer than expected, leading to this error for other processes trying to access