I don't know if you have ever happened.
I have a user that use iphone 6+ , IOS version is 11.4 ,but he can't connect to Pulse secure mobiles,
But, other user can connect to PSB(Pulse Secure Mobiles), It is Strange.
I trying to reserch support platform, but it is Compatibility ,as following:
I don't know why, if have any method, tell me, Thank you very much.