Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I advise you to go into the Settings, then the Network Settings, and make sure that one, or the other, of these two is switched Off (as appropriate, depending upon which service you wish to make use of):
- either the WiFi should be Off,
- or the 2G/3G/4G data service should be Off.
When both are On, one can interfere with the other.
(And of course, when both are Off, you don't have any internet access in that case!)