I did the latest firmware upgrade today on my mini and now my iphone 6 won't connect to the controller.  With the controller not connected to the iphone, the controller will connect to the mini.  But when the iphone is attached, it will not.  Selecting "connect to aircraft" under the control settings, gives an instant response of failed to connect.  So assuming it must be failing at the phone, as it responds to fast to have attempted to connect.

After the firmware upgrade, I did update DJI fly to the latest version.  Connections failed before and after the Fly upgrade.  
I validated under DJI Assistant both the mini and the controller have the latest versions of firmware.  And I did a refresh on the controller, but had no impact.

I am using an iphone 6S with OS version 12.1.2.
Before the firmware upgrade I had no issues.
How can I resolve this?

Hi Jeff, We're sorry for the trouble that this has caused. Can you please provide us a short video sample and screenshot showing the error message for better assistance? Also, If you have a spare compatible mobile device that we can try to use this will greatly help us to further isolate the issue. Please keep us posted. Thank you!

There wasn't any error message, the controller with the iPhone would just not find/connect to the Mini.  Sorry this is the only compatible phone I have.
I updated the OS on the iPhone 6S to 14.7.1.   That seem to resolve the issue.  This has been very frustrating, This is the last time I will update the firmware or the fly app.