Hello, I am currently in Shanghai doing an intenship, I have an X2 visa duration of stay 180 days.

I am a student back in my home country and as a requirement to have my degree I need to do an internship program. I want to extend my x2 for another 180 days I went to the public security bureau and the information guy told me I can not extend my x2 and he doesnt even know why i got a student X2 because i am not a student in china, even though i explain to him that i am still enroll in school in my home country.
Can you please advise which options do i have or what can i do to be able to stay in PRC for another 180 days to finish my internship.

thank you!