Clear blue has always worked for me 3 days after a missed period so I would trust it being as that’s 26 days your levels should/would have been high enough for it to pick up. Those ones are for early testing too so not sure about other people unless they somehow got a faulty one.

By 26 days after, you can trust the test.

I’d take another, not a digital but maybe just a pink dye test.

I didnt get a positive pregnancy test until my period was a month late. But I've also been 2 months late and not been pregnant.