Plugin won't allow me to select my connected Instagram profile

I have just installed the plugin, but the latter won’t allow me to select my Instagram account which already connected.

I am getting :

Notice
Unfortunately you have no network selected. Please authorise your network-login first at Blog2Social to publish your post. Please select at least one network.

on page :

http://www.mywebsiteaddress.com/wp-admin/admin.php?page=sentNetwork&postId=336176&lang=en

which means that I am not able to even test post to my Instagram profile. The checkbox before the Instagram button on the above page, is simply “unckeckable”, which makes it impossible to select an already connected network.

So , my question is this: how do I move on to ,”Plans & Pricing” , when I am not even able to test the product? I am assuming that the above experience is probably an oversight from the plugin developers (, if not, then it is not fair – for a software product must be ‘testable’ before purchase)

https://wordpress.org/plugins/blog2social/