Even if your customer has your pass installed in their Apple Wallet, and you have added a location based message to your pass templates, they may still not see the message.
The most common reason is that your customer has chosen to not share their location. They can choose not to share their location with any app on their phone, or not to share their location with Apple Wallet or not to share their location with your card in Apple Wallet. It is their choice and you cannot force them to choose.
You or your customers can find out more here.
If you have confirmed that your customers are sharing their location with Apple Wallet and your Pass then your GPS coordinates may not be accurate. This can happen when the address you typed in the Add Location tool does not return the precise, correct GPS coordinates that you want to trigger a location message.
The PassKit Portal uses Google Maps to search for the GPS Coordinates of a location you enter in the Address field. You can check out the Latitude and Longitude from the Advanced View.
To check the coordinate are correct do the following:
Visit the location you expect to trigger the location based message
Stand with your smartphone in your desired location, open your browser with this URL https://passkit.com/geo/
Click 'Allow' (as shown in the image below) and you will be presented the GPS coordinate of your precise location
Take a note of these values (or take a screen shot)
Validate that these are the same as those entered in the PassKit portal
If the values are not exactly the same, you can over type the correct Latitude and Longitude (from https://passkit.com/geo/) directly into the Portal.