HELP! how to I transfer to a US high school in my senior year from a foreign country?

Please Help, So I am moving from India after completing my 11th grade. Thus, I should be enrolled as a Senior in high school in America (Piscataway, NJ). However, when I called the enrollment department they told me that I will have to repeat my 11 grade again because that is there school policy and they don't let anyone coming from a foreign country enroll as a senior. I am taken higher level college classes in INDIA (Kolkata) and went to a English-medium school all my life. English has not been my second language in school so why cant they let me enroll as a senior? Also, they said it is because i need two years of history. I have taken history in 9th and 10th grade and am willing to take 2 history courses in one year OR a night class in at a community college during my senior year or summer classes. But I cannot afford to lose a whole year of my eduction and development. This is not only discouraging but also also hinders my education and development to the max.