Stray line glitch

Hey all, I’m experiencing a weird anomaly on a font I created. Certain letters (like the D and G here) are showing these lines crossing through them, and if you zoom in on the letters they go away, but they still show up in print. It should be noted that this does not happen in Glyphs, but in other programs like Adobe InDesgin/Illustrator. Any ideas that the cause could be?


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