UT dallas EE 一直没来official AD?

大概一月份收到一封ut dallas的邮件"The MS – ECE graduate admissions committee has recommended that you be admitted to our graduate program. Your admission is not formalized until you receive an “official” letter of admittance from the UTD Office of Enrollments Services (OES). "
然后我就觉得这应该是要我等official letter, 然后我就等啊等，
结果到现在也没来？
然后我又收到一个邮件
“UT-Dallas ECE: You belong here

Dear UTD-ECE Student,

On behalf of the faculty and staff of the Electrical and Computer Engineering department, I welcome you to the University of Texas at Dallas (UTD). UTD is a young, dynamic, and rapidly growing institution of higher education located in the heart of “Telecom Corridor” in one of the best cities in the United States. Your admission is the first step in an adventure of lifelong learning that is full of many dynamic opportunities. I wanted to write to you to address three important issues. As a prospective student (or parent of a prospective student) these are likely to be key issues and so I would like to give you important information about them! ”

然后我回复过去问我已经被录取了吗？怎么没有offer？

然后收到回复，说她去check一下，然后到现在也没给我回复？

是我少交材料什么的吗？