issues with sandboxing

Hi! I have an issue with sandboxing - it gives the error that it must be enabled when I try to upload, even though I included a file with the entitlements:

Code (CSharp):

1. <?xml version="1.0" encoding="UTF-8"?>
2. <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
3. <plist version="1.0">
4. <dict>
5.     <key>com.apple.application-identifier</key>
6.     <string>QIBCR75TK3.com.bgsmac.stickmantankbattlesim</string>
7.     <key>com.apple.developer.team-identifier</key>
8.     <string>QIBCR75TK3</string>
9.     <key>com.apple.security.app-sandbox</key>
10.     <true/>
11. </dict>
12. </plist>
13.  

I included it next to info.plist and called it com.mycomany.myapp.entitlements.plist

please help!