The ninth is the same note in the scale as the second, and I was taught to use sus9. I have never seen a sus2 in sheet music, or in my lessons.

(Maybe this is a Canadian thing? Or a Royal Conservatory of Music theory class thing?)

I've also seen suspended chords with a seventh, like C7sus4. (C F G Bb)

(Maybe it's a piano thing? Pianos have more notes available at once than a standard-tuned guitar does.)

When I was talking about resolving the chord, I was talking about the classical music theory that I've learned.

Suspended chords are used by classical composers to add tension to a chord progression. The tension then resolves as the suspended note moves to the third. You hear it a lot in Mozart.

I don't know a lot of folk music. or guitar music, and would be interested to find out if guitar sheet music uses sus2 in place of sus9. (And what country you are from, Luther?)