I entered US June 11th this year.The date on my I20 shows my study starts on June 18th. But after arriving, i didn't enroll in summer classes, my department advisor also advised me to take fall semester classes.And I didn't know I must enroll to maintain my status. Then I was informed that my SEVIS record was terminated. My university issued me a new I20,I paid SEVIS fee and got a new SEVIS number. I went back to China three days ago and will come back this weekend. My visa is still valid,I just got the visa two months ago. But the problem is the SEVIS# in new I20 is different from the SEVIS# in my old visa. I don't know if it's gonna cause some troubles when i reenter US. My department wrote an official explanation letter for me, I also got funding from department.Thank you.