S7 Call Barring Green Circle - How can I remove?

[Peakey]

I wanted to block incoming calls on my Samsung Galaxy S7, however, when I load up the screen containing the barring options, I am presented with a 'Green Circle' in the middle of the screen and I'm unable to move the individual slider for the relevant option that I need to select.
I have tried restarting the device on several occasions and am still struggling to find a way around it....
Any help would be greatly appreciated. Thanks in advance.

Android 8.0.0

 

[B. Diddy]

Welcome to Android Central! Is that an animated circle, like a "Loading" symbol?