Hulu Live depends on geolocation services, which means that the "location" of TextNow phones for this particular purpose is in Dallas, Texas. To get local content, enable "location sharing" to Hulu.
For iOS users, you can find that setting under the Settings App > Privacy > Location Services. Make sure Location is turned on and enable Hulu in the list of apps.
For Android users:
1. Make sure your Location is turned on in your main Settings app.
2. Tap on Apps in the Settings menu, and then tap on Permissions.
3. Tap on Location, and enable Hulu in the list.