Please kindly follow these steps to try binding it again:
1. Make sure your Mesh is not power off--------Please turn on Mesh by pressing power button and holding it for 8 seconds till a blue light come up, if Mesh could not be turned on, that means it's out of power, please recharge it at first

2. Turn off Petfon APP and then turn it back on

3. Turn off Bluetooth and then turn it back on

4. Open PETFON App(the APP might ask you if you permit Petfon to use your Bluetooth, location,microphone,camera and send you notifications. Please always click "YES". Since these options are all important in your use. If you clicked "no" for any of them, you could delete Petfon APP and download it again)

5. Please go to Petfon APP▶Menu▶Devices▶"+"▶Mesh. and try scanning Mesh again.