My iPhone network is locked

What do you mean by locked? You can't change the network or it isn't functioning properly?

See if anything here helps. 

Connect to Wi-Fi on your iPhone, iPad, or iPod touch

Troubleshooting Wi-Fi issues in IOS.    

Some things you can try. Do you have access to another WiFi network where you can try? That has worked for several people.

Try a restart.

Restart your iPhone, iPad, or iPod touch         

Try a forced restart.

Reset Device.