Question about clear blue digital pregnancy test.

Amber • My baby girl born December 20th ‘19 🥰

The test I just took said not pregnant. Me being curious I opened it up even though I heard you shouldn't ever open it because there will always be two lines. I opened mine and I only had one strip in it. This is what it looks like. This is invalid now or did this test just not catch this ? It's actually blue not just a clear kind of line.

This was the only strip. Do they always have two lines on them ?