I used to have a Ryzen 1700 on a ASUS ROG Crosshair VI Hero x370 board.
Even with GSkill FlareX 3200 MHz CL14 RAM it was a PITA to get it to run at rated speeds on the 1st gen Ryzen mobos with DOCP.
I am guessing OP is facing similar kind of issue where the RAM defaulted to its base speed...