RBR50 not seen by ORBI App...

Hello... I can't get the Orbi App on my iPhone and IPad to connect to my home ORBI wifi mesh system.
As a result I can not manage the system.

The wifi system appears to operate normall but I'm unable to utilize the App to manage the system. 

I can't determine exactly when the problem started but it's been going on for at least the last four months. 

I have followed all of the app instructions with no success.

I have deleted and re-downloaded the Orbi app with no success.

I have reset the RBR50 router and set up a new system with no success. 

I have accessed the system through the ORBI "orbilogin.net" site. Some options in the app are not available through the website. 

Thank you.