If your visa is delayed in being issued, please inform ISS, your on-campus employer and your academic department. If the reason for the delay is because of administrative processing, please note that ISS and Texas A&M University cannot speed the process up.
Delays in visa issuance could be caused the situation in the country, status issues, country of citizenship or major. If you are a STEM (Science, Technology, Engineering and Mathematics) major, then you may want to have information about your research available. A letter from your academic advisor explaining your program or research subject in plain English at the time of your interview may be helpful.
If the delay is caused by administrative processing, please be aware that there is little that University can do to find out what is causing the delay. The Department of State will not release information to the school or to anyone besides the applicant. The National Visa Center (NVC) is available to answer questions concerning nonimmigrant visas. You can contact the NVC at 603-334-0888 from 7 am to 12 am EST, Monday through Friday (excluding holidays). The Department of State recommends you wait at least 60 days from the visa interview before inquiring about delays caused by administrative processing.
According to the Department of State, “Most administrative processing is resolved within 60 days of the visa interview. When administrative processing is required, the timing will vary based on individual circumstances of each case.”
https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/administrative-processing-information.html