Views:

1.    Open Settings app, choose Mobile

Settings  Mobile

2.    Up the top, Ensure Mobile Data is turned ON

Mobile Data

3.    Scroll down to “Use Mobile Data For” section and ensure Mobile Data is turned on for “Business” (with Skype for Business icon next to it)

Data For

4.    Scroll to the bottom and ensure “Wi-Fi Assist” is turned on
 

Wi-Fi Assist