If you have an alternative browser like UC,try and see if it is working,or the default browser. Are other apps that require an internet connection working? If they are also not working then It could be poor network signal,if it is not the signal,then probably you need to reinstall opera. But before you do that try a simple fix which I always use- pulling out and reinserting the battery or pressing this combinition of keys- alt + right-shift + del simulataneously
