Hi Zoriana,
Can you try to
to install rlang from CRAN
install.packages("rlang")
and see if that fixes ist.
Cheers, Bernd
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Can you restart Rstudio and make and install from a R (before loading any package and be aware that you also do not start with a workspace loaded (as this might be already have some packages loaded). Make sure all Restores are ticked off before you restart Rstiudio (and once installed tick the again so you have the restore option again).

So a fresh restarted R with no loaded packages and then try to install rlang.
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