Are there any examples of a language losing tones?

Pretty much title. I know that there is a large body of documentation surrounding what types of changes result in what tones, but I can't think of any way for a language to lose its tonal system without just conflating them all with each other. (Neutralization?) So I'm very curious if there's any precedent for this, and if not, does that mean that a tonal language is a sort of final stage that a language can never move out of?