My unarmed strikes on my monk only show the damage as the strength total, not the dice to use, that being said, my monk is 12 monk 4 barbarian. 

As part of your levels in barbarian, are you wearing any armor, wielding a shield, or using a weapon that's not a monk weapon?

The section on Martial Arts specifically mentions this:

You gain the following benefits while you are unarmed or wielding only monk weapons and you aren’t wearing armor or wielding a shield:

If you're using any of the above items, Beyond would likely automatically disable the unarmed strikes application of Martial Arts