In the song's refrain, there's another example of a common verb used in a secondary sense.
Si dos ya no se llevan bien
If two don't get along [well]
Caption 11, Jeremías - Uno y uno igual a tresPlay Caption
The first definition you'll probably learn for the common verb llevar is "to carry." Learn the nuances of this versatile verb and you'll find this construction:
Llevarse bien/mal con alguien
"To get on well/badly with somebody"
For more examples -- and more nuances of llevar -- you could check out:
ThoughtCo. > Spanish language > Using llevar