After updating my iPad Air to iOS 11.1.1, my iPad failed to activate giving this error "the iPad could not be activated because the activation information was invalid. please try again later". What can be causing this problem

I am going nuts due to this issue since couple of days! I think mine was running successfully on iOS 11.x and then I did factory reset couple of days ago and since i wasn't able to activate it! I am not able to talk on chat support as my chat support package is expired. Me and one of my colleague had serious discussion about this, we had a doubt that Apple will put some serious bug willingly so that after few years old device user will have to upgrade to new device willingly or unwillingly, although I believe its highly unlikely Apple will do such thing! My effort to connect with chat services was useless , Apple support on twitter help me to generate case ID, but i think even if they help me with case ID i will have to pay! 😠 😟

Did you find any solution?!