Save doesn’t work?

Since a week or two I notice that this plugin doesn’t work as it used to be. I am getting bad results on Pagespeed Insights, before it was more than 95 on each website I have using extended version. What is strange that when i try to edit my settings and hit save, all my settings are getting back to default. I can’t edit anything, it must happened after some update, so it looks like optimization doesn’t work.