I need help associating a IoT Core Thing name

Hi,

I am getting an error when I want to associate a client device. I followed this procedure

Associate client devices to a Core Device in the target Thing Group Create an IoT Core Thing certificate: IoT Core Devices >> Certificates >> Create >> download Go to AWS IoT >> Security>> MoonGreengrassV2IoTPolicy >> Edit active version and add the json from the thing-inverter-policy.json file Attach policy to Thing by selecting the policy above Greengrass>>Core devices>>MoonCore>>Client devices Associate a client device. The Name must match IoT Core Thing name: Inverter Once deployment is complete, the MQTT Endpoint & MQTT Client ID will be visible under IoT Core >> MQTT client Manage endpoint>>Add MQTT broker endpoint Create a IoT Rule

but I get this error - We can't associate your core device, Inverter, with itself. Enter a different AWS IoT thing and try again.

when I try associating the thing name