1. Go to google.com and ensure that you're signed into the Google account that you created your Google Business Profile with.
2. Type "my business" into the Google search bar hit enter.
3. You should see a box towards the top of the search results that says "You manage this Business Profile" (you may have to scroll down a little bit. Click on "view profile".
4. Click on the three dot menu button in the top right corner of the "Your business on Google" module.
5. Select Business Profile settings
6. Click on Advanced settings.
7. Your Business Profile ID is the number at the top. Click "Copy ID" to copy the number and paste it in your correspondence to Google Support.