Does it work with Arduino and soft UART Port?
We are interested to know how have you managed to make it work.
Unlikely to make any difference with this problem after OP identified the problem.
So, you are not telling the story/history of trouble shooting, and you are also not posting the Arduino Codes.
Thank you for the patience you showed to get your instrument fixed automatically!
I think OP did that back in post #28
He eliminated the trailing LF when sending the command.