May be there is a problem in my boot program ...when i try to reset my phone its only show the nubia logo..but reset is not done..
If it still won't start after a few tries, I think your best option now is to factory reset it. Factory resetting your phone will delete all the files you saved in your phone. I hope you have back up. To factory reset, follow these steps:
If you think this is not an option for your because you have important files saved in your phone, please do contact ZTE as they may have a less drastic option.