I have a very similar machine with the same problem in my shop for a few years. One day I will get to it and figure out why it will not work. Very nice looking typewriter.
Hmmm... a challenge then :)
Sort of guessing it will be something very straightforward like a tiny gummed up spring that needs a drop of solvent to free it. I'm not 100% up to date on Royal portables (mine don't come out to play much) but one common issue I have found is that the link bar which sits underneath the keys and makes each keystroke trigger the escapement can rest too close to the table the machine's sat on. This is because the feet are flattened or missing and there's insufficient clearance for the link bar (my name for it) to move fully. Sit the frame on a few blocks and try it, if only to eliminate that as a problem.
Thanks Rob for suggestions - it is not the clearance though.