Can't seem to make nmf work in R, I keep getting a method error.

[Mikaelsauriol5]

library(NMF)
textes <- tm_map(textes, stripWhitespace)
textes <- tm_map(textes, tolower)
textes <- tm_map(textes, removePunctuation)
textes <- tm_map(textes, removeNumbers)
textes <- tm_map(textes, removeWords, stopwords("english"))

tdm <- TermDocumentMatrix(textes)

P <- nmf(tdm, rank=2)
Error in (function (classes, fdef, mtable) :
unable to find an inherited method for function ‘nmf’ for signature ‘"TermDocumentMatrix", "numeric", "missing"’

I've seen people use nmf like this, i'm not sure why it isn't working for me.