UT Dallas I20 denied

I have been admitted to UT Dallas and achieved $6,000 AES scholarship per year. However, last week, the university has denied my I20. I have filled out every blank and submitted all supporting documents. Why do my I20 still be denied?

Student visas may be denied for several reasons – usually it has to do with doubts that you can actually afford and American education and/or that they doubt you will actually return to your home country after you get your degree.

You need to ask the Designated School Official
ISSOProspective@utdallas.edu

https://www.utdallas.edu/isso/i20-receive/

Apply for your Form I-20

A Form I-20 is required by the U.S. Department of State as a part of an F-1 visa application. It is issued by each university or college who admits you as a potential student in the United States. If you receive I-20s from more than one school, you will have to choose which school you will attend prior to the visa interview and supply that document to the visa officer.To be eligible for a UT Dallas I-20:
Meet all eligibility requirements and be admitted to a UT Dallas degree seeking program.
Submit the following documents to the International Student Services Office (ISSO) through iComet.
UT Dallas Financial Affidavit.
Financial documents. See the (Estimate Expenses for I-20)
Bank statement on bank letterhead, no older than six months.
UT Dallas TA/RA letter, if you have been granted an assistantship.
UT Dallas Scholarship letter, if you have been granted an scholarship.
Copy of the pages in your passport that contain your picture, name and date of expiry.