Please find your APN settings in Settings -> Mobile Data -> Mobile Data Options -> Mobile Data Network.
To change the settings, tap fields in sections CELLULAR DATA APN and LTE SETUP APN and enter globaldata (one word small letters).
Please leave other intact. The settings should save automatically.
If you edited your APN settings before updating iOS, these settings will reset to the default values. You might need to reapply your settings after an iOS update.
To revert to your home carrier's default APN information, go to Settings -> Cellular -> Cellular Data Network -> Reset Settings.
After restart please check that: Data Roaming, 3G mode enabled (turn OFF 4G/LTE, voice and data only option) and HotSpot feature OFF and try connection.