Are you referring to a pdf file you attached to your cover letter? You should still be able to see it from the Proposals> Active Candidacies, then click on the name of the post and expand Cover Letter field.
I'm not sure if this is what the OP is referring to, but when you send your (one file only) along with your proposal, the name of the file does not appear, only the reference to wherever you store it. The actual name only shows after you have sent your proposal, when it's too late to do anything about if you have sent the wrong one!
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