I am having the same issue, just installed the doorbell today. It is getting 16- 18 volts AC not DC as someone said above. Slow flashing yellow but no “Ready to Connect” , no QR code scan. Does anyone from Wyze monitor these forums?
I had this exact problem because I didn’t connect the fuse to my existing doorbell chime. I connected it to the security system speaker from the previous owner thinking it was the doorbell chime. Make sure you connect that white fuse correctly!