Please help me with my phone

After updating to ios 12 using itunes i cannot activate my device. In my phone this happens. After connecting to wifi, when i click next it didnt display activation lock which i should i fill in my icloud account but instead its just a second to display "Unable to activate" "An update is required to activate your iphone." I also tried connecting my phone to itunes again and there is no display on the app. Also my phone cant read my simcard and even i remove my sim the "No service" display is not changing to "No sim" pleeeaaassee i really need help.