Check your location members. Your installer is probably listed here.

You can also check for any stickers on the chargepoint or in the fusebox to find the name of your installer.

It's important to take a few steps before your installer can help you.

Give them your chargepoint ID. It's found in the app or on the side of the charger.

Give them data access to your location.

In the end, your installer knows the installation throughout. They will have an installation report, know how the charger is wired up, how it's connected to the internet and all other details that make troubleshooting a lot easier. This is why, after trouble shooting, reaching out to your installer first is often the quickest way to solve any issues you are having.