Re-boot changes sound settings on my apps KeyOne with Andriod 8.1

[Android Central Question]

I have my setting to have sound only for calls, and all notifications to all apps the sound is off. But when I reboot my phone to clear the systems memory which I do every day. I found out the apps starts making sounds for the notifications of the apps installed on my phone,

Emails from two accounts my personal and work accounts, my network fing app, and others making me crazy with every single sound when I get loads of notifications one after other....

How I can make my phone keep all settings for all apps to be silent except with my phone app.

Thanks for any advise...