Try setting the “Sender” field as well as the “From” field. The sender field was designed as an option to handle transport problem notices when "Send" and "From" differ.

From the RFC 822 Standard for the format of ARPANET text messages

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The "Sender" field mailbox should be sent notices of any problems in transport or delivery of the original messages. If there is no "Sender" field, then the "From" field mailbox should be used.

The "Sender" field mailbox should NEVER be used automatically, in a recipient's reply message.

If the contents of the "Sender" field would be completely redundant with the "From" field, then the "Sender" field need not be present and its use is discouraged (though still legal). In particular, the "Sender" field MUST be present if it is NOT the same as the "From" Field.

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Never confuse the finger pointing at the moon with the moon (Fallacy of Misplaced Concreteness)