one of my friend is in need for help. she came to USA as an student after her second semester she had to leave USA because she had to go through spine surgery. she has took medical absence leave. SO the problem is here, she stayed in Nepal for more than two years and now she is trying to come back to  USA. She has unexpired visa and I20. Does she need to apply from the beginning? or she can just come with the unexpired visa? I looked online and found out that the sevis number for the students who takes leave for more than 5 month gets cancelled. any advise will be very helpful and thankful.