Spinner does not change PLC value

I am working on a new PID control screen and the spinners that I have put on do not change the online value in the PLC. The spinner does apear to read the value and change it on my PID screen but doesn’t write it to the PLC. We have Version 7.5.0
Thanks.

Do you have the ‘Bidirectional’ option ticked on your value binding?

Also, if you’re working in the Designer, ensure that Gateway communication is set to read-write.