Thumbnail size problem

Hello,

When I set the List category post as a widget in my right sidebar and I try to choose full, large or medium size thumbnails, the system seems not to be able to set the dimension I’ve chosen, and after the settings update it sticks to “thumbnail” size.

I can send you some screenshots by email if you need.

Could you please help?

Thanks
Max

https://ww.wp.xz.cn/plugins/list-category-posts/