5800 won't connect to internet - help!

Question

My 5800XM has stopped connecting to the internet.  If I go to, say the Ovi Store, I get the frot page, but instead of going to the Store, it returns to the previous screen.  The same happens with other websites, too. 
The phone usually asks how I wish to connect - WAP, wireless network and so on, but it is no longer doing so.  I do hope I have just inadvertently changed a setting or something, as I have just got my phone back from being repaired, which took nearly 3 weeks...!
Any advice very much welcomed!  Thank you.

Answer 1

No, I'm afraid not. My phone died completely for the 2nd time shortly after it stopped connecting to web pages. I tried everything suggested by chanchan05 and jjegan. I am going to be getting a new phone (another 5800XM) in the next few days, with any luck.
Can you get on to any websites at all? I was able to go on to Youtube, and occasionally ovi mail, but absolutely nothing else. The fact that I was able to get on to those suggested that it wasn't the internet settings as such, but something inside the phone wasn't allowing me to get on to most sites.
Is yours doing the same thing as mine, by returning to the screen from which you select the internet after a brief pause? Mine did, for a day, work well, asking me if I wanted to connect via WAP, the service provider's gubbins or by wifi, but it soon gave up even asking.