Resetting the network settings on your phone can resolve network connection problems.
Note: Performing this action will delete all network settings, including saved Wi-Fi networks and Bluetooth connections. It will not delete any apps, data, or contacts.
Go to the Start screen. Drag the bar up to the edge of the screen.
Tap Settings.
Tap Network and Internet.
Tap Mobile network.
Tap Advanced.
Tap Access Point Names.
Tap the options symbol.
Tap Reset to default.
The network settings have been reset.