Message type: E = Error
Message class:  65 - Securities class data 
Message number: 016
Message text: You cannot change the issue currency
You cannot change the issue currency since position indicators have
already been created for the class in the company code.
If you want to convert all the positions to a new issue currency, you
can define and post a corporate action from the 'Convert issue
currency' category.
The change is reset.
Press enter to confirm the reset.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message 65016, "You cannot change the issue currency," typically occurs in the context of financial transactions, particularly when dealing with documents that have already been posted or processed in the system. This error indicates that the currency associated with a document (such as an invoice or a financial transaction) cannot be modified after it has been created.
Cause: Document Status: The document may already be posted or in a status that does not allow changes to the currency. Currency Type: The currency type (e.g., local currency, document currency) may be locked for changes due to system settings or business rules. Configuration Settings: Certain configuration settings in SAP may restrict changes to the issue currency for specific document types or transaction types. Cross-Company Transactions: If the document involves multiple company codes, changing the currency may not be allowed due to intercompany accounting rules.
Solution: Check Document Status: Verify if the document is still in a
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