In the last few days I've had a message pop up saying
WhatsApp can't connect using the current Wifi network. Allow this app to use mobile data
My wifi is working ok, I can use other apps with out any problems
I have submitted a feedback, with screenshot
Error message back this morning as soon as I opened WhatsApp - BUT -Its because i'm now on works wifi. Went into settings and changed the MAC Address back to Use Device MAC and the error message no longer appears!!
So this looks like it's the issue