It looks as if it's writing MIDMARSH. I think it is easier on a new layer. I seem to recall that if you hold shift whilst using the brush they draw straight lines.
Adrian: I'll see whether Affinity works the same way. Trying to draw straight lines on a touch pad isn't easy.
If Affinity has Paths then the easiest way is to click shift click to give you a path then select stroke path.You may have to experiment with brush size and jitter.
Thank you for visiting. Hope you enjoyed the pictures. Any comment, or correction to any information or identification I get wrong, is most welcome. John