QUICK SOLUTION. RESET YOUR NETWORK SETTING. THEN RECONNECT TO YOUR MAC. THEN, IT WORKS. I was same. I changed to new phone. and I transferred from previous iPhone to new iPhone. I installed my testing app on new phone, app didn't work. and I got messages from both sides. Mac and phone. unable to verify .... internet connect.. vpn setting. anyway. now I am fixed. I hope it helps someone who has the same issue.