A typical horizontal blind has two kinds of "strings".

The pull cords and the "ladders" that keep the slats in place.

Each pull cord has two ends: one attaches to the bottom rail
and runs entirely through the rout holes in the slats – top to bottom.

The other pull cord end runs entirely through the headrail cradle
(up from the slat rout holes) towards
the control side – then through the clutch and out (either joining
the remaining pull cords in a plastic cylinder, or it runs out free alongside
the other ones (2-3-4 pull cords) – into a wooden tassel you'd pull on).

The "ladders" end up with their ends in the two sides of a small drum
that's sitting in the headrail plastic cradle. Make sure it is so.
The bottom two ends (front and back one) attach to the bottom rail.

Since your slats tilt, it's most likely your pull cords in the horizontal blind.

If only one is out, trace the other one or two and see how they run.
Then, set up the one in question accordingly.
Level as needed.

How this helps you Stan a bit.

Kate & Pete