Ok I tried it on Edge browser and the notification sound worked. The gmail is a work/business account. So it appears something wrong with Chrome on my Windows PC. I tried Chrome on my Mac and it worked.
Try clearing the cache and data in the Hangouts app. You can do that by going to your Android settings > Apps and Notifications > Hangouts > Storage > Clear Data (or Storage) and Cache
Is your device's microphone working in other apps? --> Yes Works for another aps Are you sure your microphone is enabled? --> Enabled In the call try turning off your microphone, then turning it back on again. --> I have doing this but the problem not solved Are you making a phone call to a
