I'm sorry, but your lack of punctuation is making it very hard to figure out what you're asking, Leila.
Are you saying that you are not able to add an MP3 to your project?
We always recommend converting your MP3s to WAV files before you load them into Premiere Elements. It resolves a number of potential issues.
You can export MP3s as WAVs with this free audio editor.
Sorry about the punctuations, I'm very frustrated at the moment. I will try your method and hopefully resolve my issue, thanks for the advice and will get back with you on the results.
Also, when you Opened your Project, did you get a dialog box asking "Where is file ____.MP3?"
Let's rule out a broken link to the MP3 right away, as it could well be something else causing your problem.
Thank you so much for the advice! After so many hours of trying to figure this out, your solution finally gave me some peace! Thanks again.