Why can't Windows 10 update on my phone?

[Windows Central Question]

i have no idea about this question

my phone model is lumia 525.i update windows 10 via windows insider then I update windows 10 while my phone restart and process to instrall suddenly its turn off then automaticly start and process to instrall and then trun off its can not startup and update windows 10 how can I startup my phone . I think windows 10 is not fully update to my phone how can I solve my problem..my previous version was windows 8.1.. please help me!!