Labia is a fantastic piece of Spanish slang that means "sweet talk" or "smooth talk". It refers to the clever, charming, and sometimes deceitful words someone uses to persuade you, similar to having the "gift of gab".
In the song, Becky G warns a potential lover, "no me des labia" (don't give me that sweet talk). She's saying she's wise to his game and won't be fooled by empty flattery, reinforcing the song's theme of fierce independence.
Becky G puts her cards face up on the table right away in "NI DE TI NI DE NADIE": she wants to have fun, but she is nobody's girlfriend. From the opening warning, "Si quieres probar puedo ser tu mejor secreto / Pero no te enamores de mí" ("If you want a taste, I can be your best secret / But don't fall in love with me"), she sets the ground rules. Sweet talk will get you nowhere. When she says "no me des labia" ("don't give me smooth talk"), she uses the Spanish word labia, which describes that slick, persuasive sweet-talking people use when flirting. She already knows all the tricks, so smooth lines are useless.
Her humor really shines when she describes her love life as completely shut down: "Mi corazón dice cero sentimiento / Fuera de servicio, lo dejé en mantenimiento" ("My heart says zero feeling / Out of service, I left it under maintenance"). Putting your heart in "maintenance mode" like a broken elevator is a hilarious way to say you refuse to catch feelings. Even if the other person promises the universe, she shuts it down with "tu corazón que se calme" ("tell your heart to calm down"). For language learners, this track is packed with everyday conversational phrasing for setting firm boundaries without drama.