Error message: dfm() and corpus_reshape() 'only works on corpus objects'

I get repeated error messages that a corpus object is not a corpus object.
I cannot understand what is wrong.
In R studio I created a small corpus of 2 text files. This is a sample of their content (yes, the files have empty lines):
' Strategy


measures for its implementation
corpus1 <- Corpus(DirSource(directory="C:/Users/etc."))
I checked corpus1 and it looks fine

corpus1 <> Metadata: corpus specific: 1, document level (indexed): 0 Content: documents: 2
However, I get an error message, when I try these commands.

corp = corpus_reshape(corpus1, to="paragraphs")
Error: corpus_reshape() only works on corpus objects
dfm=dfm(corpus1,remove_punct=T, remove=stopwords("english"))
Error: dfm() only works on character, corpus, dfm, tokens objects.