Open Mijia, navigate the options menu at the bottom, and select the Mijia menu on the left. Then you can see in the Mijia interface that some options will pop up after long pressing the binding device, and there is a delete option in the lower right corner. You can delete the bound device and click Delete. After clicking the delete option, you can see that the device is being deleted at the bottom, and you need to wait for the deletion to be completed.