my iphone 3gs had lower version of iOS and i wasnt able to download watsapp. during downloading its says update iOS 4.3 and i did connect my phone with iTunes. and i did fully update with 6.1.3 version. now I not able to activate my iPhone3GS after update

my iphone 3gs had lower version of iOS and i wasnt able to download watsapp. during downloading its says update iOS 4.3 and i did connect my phone with iTunes. and i did fully update with 6.1.3 version.

now I not able to activate my iPhone3GS after updated to ios6.1.3. The message said the activation server is unavailable but it has been unavailable for more than 24hours. It's abnormal, please help. Thank you!

i need the permanent solution because i saw a lot of cideos to jailbreak but i really wont do that.