ITC-308 can't change factory defaults

I have a new ITC-308, I am not able to change any of the factory deftly settings. For example, I got into settings mode and change TS from 25 to 30 degrees celsius, once the display stops flashing it goes back to SV 25 degree and not SV 30 as I had just set. Can you advise how to fix this issue?

Hello,
After the setting is completed, please press and hold the ‘SET’ button to save and exit the setting, otherwise the setting will not be saved.