Guitar string indicator problem

To play a guitar note C# written below the staff you can use either the 5th string or 6th string. I want to indicate 6th string. Using the Properties window Notes and Rests group with the C# highlighted in Write mode, Dorico does not offer the 6th string as an option.
What’s the remedy?

Correction: I used the String Indicators group, not the Notes and Rests.

And, of course, it worked right. Problem solved.

Do you have the Dorico Pro or SE? Not sure if the scaled down version has this, but in Pro, all string indicators can be found in the Playing Techniques panel.

Thanks. I have Dorico Pro 3.5. Wow. A lot of this is so different from Finale, Sibelius and MuseScore! That’s not a value judgment, just an observation,
Some things have been easier than others to penetrate. Overall Dorico gives me, sometimes grudgingly until I call in you guys, more of what I want than I expected. The great majority of this is awesome.
Master Frames wrung me out for the last few long days, and I have not quite given up but came close to it. Much emphasis is given in the various tutorial materials on the details of graphics etc. That part is easy and smooth now. What has been really challenging has been learning how not to have Dorico destroy my work. I would quit Dorico and come back to find no trace of any of my work. A simple Save… doesn’t seem to appear. Dorico lets me quit without warning me of the impending destruction or what to do about it. I was looking for a way to tailor My Dorico master frames to my tastes, choice of my masterpieces available by default at a click, and have the out-of-the box objects (with those nasty little red triangles) to recede into the background, recoverable at request. What I seem to have is the opposite. I’m sure that everything about Master Frames makes perfect sense to many people. Sadly, I’m not one of them.
I wrote firmware for a living, which gives me some inkling of the size of this task Dorico has taken on–massive, huge, far bigger than anything I did. Knowing this, I will stick my neck out far enough to suggest that Master Frames needs a little more work.

I’m pretty sure you mean Master Pages rather than Master Frames; but yes, they take some getting used to, and remembering that the Apply/Close buttons are in the upper right hand corner rather than at the bottom for the Master Page editors can lead one to forget to click there.