Facebook Messenger calls problem on Lenovo Essential tablet

[arbagai]

Hello mybroadband members,

I use Lenovo Essential tablet. I have a problem that when someone call me via Facebook Messenger, the table only vibrates, it doesn't call any sound at all. But the sound for Facebook messenger's notification like - incoming inbox message, miss calls, still works. Looks like only the ring tone for calls is not working.

what I have tried that doesn't work:

• Clear data for Facebook messenger.
• Re-install Facebook messenger from google play, also tried install latest version messenger apk from androidapksbox and also beta version from apkmirror.
• In Facebook messenger -> Notifications & Sounds, I enabled everything.

I check some articles say:

Go to Settings-apps- messenger. In there will be an option that says notifications. For some reason it was set to low priority and silent.

but I can't find any thing (I see "Show notifications" checkbox, but it has already been checked). Here is the picture:

So how can I enable ring tone for calls in Facebook Messenger?