As far as I know you can't update the phone over a mobile connection if it is a large update . I've tried many times in the pass and the phone always tells me it will resume the download once I'm on WiFi. That being said you can use your SIM in another phone ,since it seems that you have alot of data . Then use that phone as a mobile hotspot and connect to it . Your phone should update . Or connect to your WiFi router at home. Other than that , there's no known way to update a large update over cellular network right now , or that I know of .