Hello @Pelukin, welcome to the community and I'm sorry to hear about that!
Your query was translated to English, since this is a international forum.
I recommend that you start with checking that your phone isn't in Do Not Disturb-mode. Do Not Disturb is a function where all sounds except alarm and media sounds is muted, and you can access it by pressing the volume down button on your phones side. You can disable Do Not Disturb by pressing the volume up button. You can also enable/disable Do Not Disturb under the quick settings you reach by swiping down from the top of the screen twice. The Do Not Disturb-mode is identifiably by a notification that looks like a circle with a line in it in your notification field. You can read more about it and see the icon here: https://support.sonymobile.com/global-en/xperial1/userguide/do-not-disturb-mode-settings/
If your phone isn't in Do Not Disturb mode, make sure that you have assigned a ring tone and a notification tone to your phone. You do this under Settings > Sound > Phone Ring tone, and Settings > Sound > Notification Sound. You should also take a look at the volume settings here, so your Ring Volume is on.
You can also test your phones speaker in Diagnostics. You will find Diagnostics under Settings > About Phone > Diagnostics > Loud Speaker/Ear Speaker.
Keep me updated! I would love to hear how it went.
