The handrail is round section then the behavior is correct as there is no edge basically. So you've option either to use rotate view OR try align horizontal/vertical to another view.
Is this in the drawing only?
click 'front' 'top' or 'right' standard views in your part model to check.
it might be that your part is not aligned to the standard planes.
Can you reset your standard views on the model, it looks like your part is 'floating' and the drawing is looking for front right and top planes to align.
just a thought.
For weldments I use relative view for odd angles (assuming it is possible, would need to see part).
Or you can draw a horizontal/vertical line, pull the dimension, rotate the view and delete the line.
Thanks for your answer.
What do you mean by relative view?
for weldemnt assemblies the viwes of the separate parts take the orientation from the main assembly, so maybe what you can do is to create a new view in the Model and then apply it to the view in the drawing.
and if you attach only the separate part in the post, it will be much easier to give you the right answer.
Use the Split Line tool to vertically split the surface of the rail ( a ref plane can be used). The resultant split "edge" will then be accepted as a valid edge for the Align Drawing View command.