If your recording device has a limiter function, try turning that on. It will limit the DB input by the recording so it won't exceed a certain level. It is useful to avoid distortion in ff passages.
That would completely defy the purpose of using somewhat decent equipment that is designed to catch the full dynamic range of a piano.
There is something wrong with the set up of OP and the solution is not a dynamic range limiter when he has a Steinway B in his home.
I suspect that there is something wrong with the audio routing, like routing the digital signal back into the microphone input of the computer. Going into the computer with USB means that the D/A-converter in the audio interface is active, but maybe the recording software is set to record from the microphone input, not from a digital input that the audio interface provides.
As a first step I'd plug in headphones into the Focusrite and use the stereo monitor mode to listen for possible distortions and play with the input levels to see whether distortions occur every time or only below certain levels. If the audio interface gives you a clean signal then one needs to look at how the audio signal path is handled in the computer.
OP said nothing about his operating system, but I suspect it's not Linux, so I can't really be of help other than saying that the first thing to check is looking at the signal path as part of the audio settings of the operating system. Any microphone controls should be disabled, unless they are specifically labeled as coming from the audio interface. If that doesn't yield the necessary results, then looking at the recording software's input controls.
OP should mention the operating system, the recording software and respective audio settings for us to help him with a diagnosis.