Update issue in my samsung M02s

Stuck at update in my samsung M02s since last 4 hours. It goes from 0 to 37% and then restart automatically. (Not complete restart, only samsung logo appears) Then again doing the same process of 0 to 37% since last 4 hours. How can I solve this issue? Please suggest me options without data loss. If that is not possible, then I'm ready to try other options.