Slider settings disappeared

Hi
I tested your plugin on my test site and it worked fine. Then I added it to my production site and when I set on slider I changed settings then saved. From then the settings values have disappeared and I can’t set them anymore. Any idea what happened ?
If I set a new slider it’s the same default settings values are displayed if I save they disappear.

https://www.ads-software.com/plugins/easy-logo-slider/