I had noticed this before as well. When you set the font for your text, were you selecting the text box, then setting the font? If so, try highlighting the text itself instead of just selecting the text box.
For some reason changing the font while only selecting the box itself is not consistent. I also make sure to use a font style instead of a manual font change, as that consistently works even when you just select the text box and change it via the styles tab.
If none of that works, attach your file here and I’ll take a look.