Interview Invite but no personal letter on app?

[lavidabroca]

I received an invite from a program, but I went back to look at my application on CaRMS... for some reason when I went to check my application, there was no personal letter. I'm pretty sure I uploaded it, but it isn't there now. I'm not sure how to proceed- do I upload my personal letter now (it would be late, and per the program description, late documents aren't reviewed), or do I just accept it and move on? I'm curious why I have an interview invite if my personal letter wasn't in there. This is a school and a program that is not my ideal, if that makes any difference. Thanks in advance.

[JohnGrisham]

Sounds like MUN FM or MUN Psych. Desperation is why some programs send out offers even before unmasking LORs