Cannot change Chime ringtone

Hi, Today I found that I could not change ringtone on my Chime (the original version, FW version 1.3.3). I control Chime via the Ring app on my Android phone (app version 3.22.1). When I select different ringtone, hit "Save Changes" I get the confimation about settings being updated. But the Chime light does not start blinking and when I test sound the default sound is still there. I tried following: - Reset chime (via the pin hole). - Restart chime. - Re-install Ring application on my phone. None of it helped. Any idea how to fix this? Cheers, Mirek