R help - Jan 2018 - plm empty model error (data is linked)

Hi,

I am trying to estimate a two-way model with both individual and time fixed
effects. I am using plm with "twoways" specification.

plm(as.integer(yvar) ~ xvar, index = c("id", "time"),
model="within",
data=dataset, effect = "twoways")

But I get keep getting the following message and I don't know what to do
about it, because I don't think anything is wrong with my indices (but
please correct me if I'm wrong on this!). : Error in plm.fit(formula, data,
model, effect, random.method, random.models,  :
  empty model

Here's the data:
https://drive.google.com/file/d/1p-LrZ3GdVhsat6xFCJ5FmmhUL9SvFAG5/view?usp=sharing

Thank you so much in advance for your help.

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