A "rejection notice" is a message or communication that tells someone that their request, application, or idea has been denied or turned down. Full definition
They often receive hundreds of resumes for one internship position, which means the numbers are too overwhelming to send rejection notices. (internships.com)
I have yet to dabble in the difficult task of sending my writing to a literary agent, but I found a lot of your advice helpful in regard to keeping my morale up as my inbox fills with rejection notices from literary magazines. (hubpages.com)
He is there when I get rejection notices and says, each time I announce one, «I never reject you.» (rubyforwomen.com)