no se olvide

don't forget

→ no
phrase Uncommon #14,982
don't forget A polite or formal command addressed to one person using usted. The plural form is no se olviden, used when addressing several people.
SP: No se olvide de traer las llaves.
EN: Don't forget to bring the keys.

Y no se olvide, la recogeré mañana.

And don't forget, I'll pick her up tomorrow.

— Roma. Ciudad abierta (1945)

No se olvide del alquiler, señora.

Don't forget the rent, ma'am.

— Las diabólicas (1955)

No se olvide el paraguas.

Don't forget the umbrella.

No se olvide que es un sirviente a sueldo en esta casa ¡Un profesor!

Don’t forget that you’re a hired servant in this house. A professor!

— Black (2005)

No se olvide del billete.

Don't forget the ticket.

No se olvide las gafas de sol.

Don't forget your sunglasses.