Bravia tv not connecting to Internet

Hi there

I have a bravia tv and when I first bought it I purchased the Sony dongle, I then connected the tv to my home network and everything was fine. Then 3 weeks ago my tv lost the Internet connection for no reason and when I check my connections the tv wifi was found but the local Access has failed and the network access has also failed.

Any advice would be very much welcomed.

Cheers
Gary