Ok then either another plugin that you have installed is blocking communication to the AITpro API Server or your Host is blocking communication to the AITpro API Server.
You can use the alternative upgrade method.
1. Go to the BPS Pro Secure Download Area.
2. Download the BPS Pro zip file.
3. Use the BPS Pro built-in upload zip installer (BPS Pro Install / Backup menu link) to install the BPS Pro zip file. DO NOT use the WordPress Upload Zip installer.