Adding Problem of Device in Aqara Zigbee App

On my Homey Pro I currently have 12 Routers in the Aqara App and a few End devices. Now I want to add some wireless switches and sensors but keep getting the message: “This device has already been added. It may be necessary to remove the existing device and add it again to Homey.” Strange, because the device was never added. I only started getting this message after updating the software to version v8.0.2. Anyone with an idea of what could be the cause of this?