Draw over other taps (can't enable Storage permission for Whatsapp)

I just upgraded my FP2 to the new Android version and I can’t view images on Whatsapp.When I click on them, I see a message that Whatsapp needs to access photos, media and files and to go to Settings and enable that, but when I do, I can’t enable Storage.
I’m then taken to the Draw over other apps menu that I can’t enable for Whatsapp either.
I’ve been looking in the manuals/forum to no avail, can someone help, please?

7 posts were merged into an existing topic: 6.0 permissions: Sceen Overlay detected - unable to change app permission bug