Not saving the updated value

I have been battling this for some time. Subscribe2 is a beautiful plugin and facing challenges in saving the updated values
1. Set default Subscribe2 page : I change the page options from drop down and save
2. Email Settings : I change the user through which emails will be sent and save.

I do not see values in both these sections taking affect. The email is still sent out from admin(that is the first value in drop down)
when users subscribe they see the first default page, not the one I had selected in drop down.

I am using W3Cache. I flushed out all the values but still it does not help.

https://ww.wp.xz.cn/plugins/subscribe2/