I’m trying to learn for my English class and I’m stuck. Can you help?

So I’m transfer student I applied to Marymount university the last semester but I accepted very late and when I tried to register for the classes there were all closed and I tried to contact the department of each class every one told me that all classes are closed and no one can do something. So I complete in UDC where I want it to transfer from. Now I have student account in Marymount and when I tried to register classes again for the spring I reserve in error message (SR) I called the register office and they told me that I have to apply again because I’m not an active student. so there no time to apply again and she told me to contact one person in admission maybe she could help me if I explain my situation.

So I need an email to explain my situation why I didn’t apply last semester and ask for her help.