"danlwd sayfwn qdymy" — might be a of each word?
d → w a → z n → m l → o w → d d → w space s → h a → z y → b f → u w → d n → m space q → j d → w y → b m → n y → b
Another known cipher: (A↔Z, B↔Y, …): d ↔ w a ↔ z n ↔ m l ↔ o w ↔ d d ↔ w → "wzmodw" (no) danlwd sayfwn qdymy
I suspect it might be — "danlwd" could be "دانلود" (download), "sayfwn" — "سایفون" (siphon?), "qdymy" — "قدیمی" (qadimi = ancient/old).
If you meant it as a puzzle, my best guess is (download old) + "سایفون"? Possibly a typo or nickname. "danlwd sayfwn qdymy" — might be a of each word
Not obviously English.
But maybe it's a ?
d (4) → y (25) if shift -5? That doesn’t match.