Message type: E = Error
Message class:  BKK_PRENOTE - BCA : Prenotes 
Message number: 055
Message text: Medium &1 is locked for certian transaction types
There are locks on the account for the medium &1 for particular
transaction types.
The system issues this warning message.
Check the locks on the <LS>Payment Transactions</> tab page of the
account.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message BKK_PRENOTE055 indicates that a medium (such as a payment medium) is locked for certain transaction types. This typically occurs in the context of payment processing, particularly when dealing with payment media formats like SEPA, checks, or other electronic payment methods.
Cause: Medium Locking: The medium is locked because it is currently being used by another process or user. This can happen if: A payment run is in progress. The medium is being edited or processed in another session. There are configuration settings that restrict access to the medium for certain transaction types.
Configuration Issues: The configuration settings for the payment medium may not allow certain transaction types to be processed, leading to the lock. User Permissions: The user attempting to access the medium may not have the necessary permissions to unlock or use the medium for the specified transaction type.
Solution: Check for Active Processes: Verify if there are any ongoing payment runs or processes
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