User X already processing contract 46...

Hi Sap gurus,

We have classic scenario and some of the Shopping cart are transformed into Purchase order automatically with program SRM_BBP_SC_TRANSFER_GROUPED. When this is done some of the PO get stuck in FEH /SAPPO/PPO2 in ECC with error that our interface user is already processing contract. It happens repeatably.

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Please has anyone any idea how to avoid these errors?

Thanks!