we know from many ahadith that laylatul al qadr happends during ramdan:

Sahih Bukhari : Volume 3, Book 32 "Taraweeh", Number 238

Narrated ‘Ibn Abbas (Radi Allah Anha): The Allah’s Messenger (sal-allahu- alleihi-wasallam ) said: “Look for the Night of Qadr in the last ten nights of Ramazan on the night when nine or seven or five nights remain out of the last ten nights of the Ramazan.”

as we know, ramdan occurs every hijri year, and if laylatul qadar hapends in ramdan, then it must occur every hijri year too.

Although we may not know the exact date of laylatul qadr we know for sure that it happens every year.

We know from many ahadith that laylatul al qadr happends during ramdan:

Sahih Bukhari : Volume 3, Book 32 "Taraweeh", Number 238

Narrated ‘Ibn Abbas (Radi Allah Anha): The Allah’s Messenger (sal-allahu- alleihi-wasallam ) said: “Look for the Night of Qadr in the last ten nights of Ramazan on the night when nine or seven or five nights remain out of the last ten nights of the Ramazan.”

As we know, ramdan occurs every hijri year, and if laylatul qadar hapends in ramdan, then it must occur every hijri year too.

Although we may not know the exact date of laylatul qadr we know for sure that it happens every year.