Same problem!!!! This is really devastating. I upgraded so I had a device with an ability to do more grad school rates HW on the go, but alas, the very app that houses my class no longer operates!!! Help!!
Yes, I am getting this too, also on an iPhone 8 Plus. Same problem with Skype too. Can't be iOS 11 related as both were working fine on my 7 Plus on the same OS. Very annoying as I'm missing out on updates from Directors and colleague on the go, and can only respond when I get back to my PC.