Debug an existing PHP script

We have an existing php script that works well. It communicate to Google via their API. We recently moved to a new host and since that time the script does not work correctly. We believe it may be a simple blocking issue on the new host as it appears the information is not getting returned from Google. The task is to find the problem with the script and get it working with the new web hosting. Possibly it might be a matter of getting a relevant port opened by the web host, or there could be some other issue. The script has worked perfectly for about 8 months until we moved, so we feel confident the issue is the web host and not some other code, but in any event that will be your task (to find and fix the problem wherever it is). The script is developed in PHP. It uses a database,but the database interaction is quite simplistic. This should be a very easy task for someone knowledgeable with php the use of Googles API.