Message type: E = Error
Message class:  ISU_GS_IN_SMS - Message class for IS-U: India localization for SMS Services 
Message number: 020
Message text: Bussiness Partner " &1 " does not have active mobile number.
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The SAP error message ISU_GS_IN_SMS020 indicates that a specific Business Partner (BP) does not have an active mobile number associated with their record. This error typically arises in scenarios where mobile communication is required, such as sending SMS notifications or alerts.
Cause: Missing Mobile Number: The Business Partner record does not have a mobile number entered. Inactive Mobile Number: The mobile number may be present but marked as inactive or invalid. Data Synchronization Issues: There may be issues with data synchronization between different systems or modules within SAP.
Configuration Issues: The system may not be configured correctly to recognize or validate mobile numbers.
Solution: Check Business Partner Data: Navigate to the Business Partner transaction (e.g., BP) in SAP. Search for the specific Business Partner using the ID provided in the error message. Verify if a mobile number is entered in the relevant fields (usually under the "Address" or "Contact" information). Update Mobile Number: If the mobile number is missing, enter a valid
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