TimeStamp not working

Have struct Message{ int switchState; String timeStamp; }message; SwitchState is sent to E220 receiver. TimeStamp only prints non-printable characters to E220 receiver. TimeStamp is populated on E220 sender by the getDateTime functio variable dtStamp. I can print message.timeStamp and see a properly formatted time stamp on the E220 sender. Have worked this issue for hours; help would be much appreciated. Regards, William