Uploading to Canva

Having trouble uploading some of my most recent fonts to Canva.com. The uploading loading bar on Canva goes for several minutes and nothing happens. Not having the same issue with older fonts. Working on Glyphs 3 and up to date. What settings might I be missing that could be impacting this?

Can you drop them onto fontbakery.com and see what errors are maybe reported?

Thanks for this, fontbakery helped. It reported empty glyphs, which were intentional - my fonts are Hebrew, and I exported these fonts with all Microsoft 1252 glyphs as empty glyphs, for compliance with Microsoft Word etc. Apparently Canva has the opposite problem and doesn’t like empty glyphs?