If you have problems with the Wi-Fi connection. This is one of the most common problems and it is really easy to solve.
How to solve it?
The first thing is to restart the device and turn off the router for 10 seconds and then turn it on again.
You should also make sure that the power saving mode is off. Since this mode disables networks when the phone goes into standby mode.
Another option is to go to Settings, Networks, Wi-Fi and forget the Wi-Fi connection. Then enter the network data again.