One of the biggest challenges with having an online business is that we are ONLINE much of the time. This means that when we sit down to work, we are being distracted by all sorts of bells, whistles, pings, notifications, etc.
One thing that I have found that helps so much is to turn on (or off) a few controls in Facebook.
On your iPhone:
open up the Messenger app
choose "notifications"
choose "mute"
select the duration
On your desktop
go to the globe icon on the upper right corner of your screen
choose "mute"
select duration
Set up auto-replies from your business page
go to your Facebook business page
go to "settings"
go to "messaging"
select "instant reply"
compose an automated message