PHP fix the shell_exec command

I am looking for a freelancer who are expert in PHP. I have got a problem with shell_exec command because it will not work when I am trying to run the command, but only one work. I'm trying to fetch the data from mysql database to output them in the variable and run the command. I want to run the command to report the emails as spam. If you can be able to fix it for $30, that would be great. I'm looking forward to working with you.