The picture you post is not visible.
Below are my experience and tips of sending command to external modbus device. Not sure is it the same issue you encountered.
When 1 trigger triggers and sends 2 commands to 1 same external device. the auto control module stops working will work at the beginning, but fail after a few events.
Then I set some delay to each command, then it seems ok as a work around.
my device comm setting, auto control setting and server log are attached in the following link.