So, since I don't want to wait for Purdue to admit me after 4/15, I chose to accept RPI's offer 3 days ago. However, I tried sending them the formal signed letter, then send them an email asking what else I need to submit before the deadline, then call the coordinator (each of them a day apart), but zero response whatsoever. Given that I have done everything I could think of, I'm starting to worry a bit. What is happening and what should I do now?