TV box is not loading data after switch from Nighthawk AC1900 to xFi cable modem

I just switch to Xfinity xfi gateway today.  I have a TV box (Unblock Tech) connected via category 5 cable, which works fine before the switch.   I cannot access several apps and it kept saying loading data and stuck.  Is there any setting that needs to be changed in xfi gateway in order for me to run the apps?