Check the members of your location. Your installer is probably listed there.

You can also look for stickers on the charger or in the fuse box with the name of your installer.

Take these steps first, so your installer can help you.

Give them your Chargepoint ID. You find it in the app or on the side of the charger.

Check that your installer has the access they need. If they handed the charger over to you, they usually still have access to manage and service it. If they are not a member, or have only basic access, invite them or give them data access to your location.

Your installer knows the installation. They have an installation report and know how the charger is wired, how it connects to the internet and the other details that make troubleshooting easier. That is why, once you have done the first troubleshooting, contacting your installer is often the quickest way to solve a problem.