Message type: E = Error
Message class:  VTX - Messages from tracking notification processing 
Message number: 815
Message text: No delivery date exists in this entry; transfer not possible
Based on the tracking data of the previous tracking event, no delivery
date could be calculated. Therefore, the delivery date was not
transferred from the tracking data.
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 VTX815 ("No delivery date exists in this entry; transfer not possible") typically occurs in the context of logistics and supply chain management, particularly when dealing with deliveries, shipments, or transfer orders. This error indicates that the system cannot find a valid delivery date for the entry you are trying to process, which prevents the transfer from being completed.
Causes:
Missing Delivery Date: The most common cause is that the delivery date has not been specified in the relevant document (e.g., sales order, delivery, or transfer order).
Incorrect Document Status: The document may be in a status that does not allow for processing (e.g., it may be incomplete or not yet released).
Data Entry Errors: There may be errors in the data entry, such as incorrect item numbers or missing information.
Configuration Issues: There could be issues with the configuration of the delivery or shipping settings in the SAP system.
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