UTF-8 dotless i in cmd - r

Question

I have an R script which was coded in utf-8. While running it in Rstudio, there is no problem with the Turkish characters. However, when I try to run it from cmd it throws an error:
Columns ÜrünAçiklama, and HataTanimi don't exist.
It gives this error because my dataframe has the columns 'ÜrünAçıklama' and 'HataTanımı'.
As you can see, there is no problem with the characters "Ü,ü,Ç" but there is a problem with dotless i (ı). I run the script with this line in cmd
Rscript --encoding="UTF-8" myscript.r
my OS is windows10
What should I do? Thanks in advance.
EDIT:
An example should be fine.
Here is my dataset. When I try to delete duplicate lines, I cannot reach the columns contain dotless i. You can try it in your own cmd with the following script.
library(readxl)
rm(list = ls())
shell("cls")
df <- read_excel("stackoverflow.xlsx")
df$ÜrünNo
df$ÜrünAçıklama
df$HataTanımı
df$HataZamanı
df_nd <- df[!duplicated(df[,c("ÜrünNo","ÜrünAçıklama","HataZamanı")]),]
Also here is my CMD output:
[1] 1 2 3 3 4
[1] "X" "Y" "Z" "Z" "Q"
[1] "A" "B" "C" "C" "D"
[1] 10 11 12 12 13
Error in `vectbl_as_col_location()`:
! Can't subset columns past the end.
x Columns `ÜrünAçiklama` and `HataZamani` don't exist.
Backtrace:
x
1. +-df[!duplicated(df[, c("ÜrünNo", "ÜrünAçiklama", "HataZamani")])]
2. +-tibble:::`[.tbl_df`(...)
3. +-base::duplicated(df[, c("ÜrünNo", "ÜrünAçiklama", "HataZamani")])
4. +-df[, c("ÜrünNo", "ÜrünAçiklama", "HataZamani")]
5. \-tibble:::`[.tbl_df`(df, , c("ÜrünNo", "ÜrünAçiklama", "HataZamani"))
6. \-tibble:::vectbl_as_col_location(...)
7. +-tibble:::subclass_col_index_errors(...)
8. | \-base::withCallingHandlers(...)
9. \-vctrs::vec_as_location(j, n, names)
10. \-vctrs `<fn>`()
11. \-vctrs:::stop_subscript_oob(...)
12. \-vctrs:::stop_subscript(...)
13. \-rlang::abort(...)
Execution halted
As you can see, I can reach columns one by one, however when I try to delete duplicate line it just says columns do not exist.

Answer 1

While I was making some research, I encountered this sentence.
R 4.2 for Windows will support UTF-8 as native encoding, which will be a major improvement in encoding support, allowing Windows R users to work with international text and data.
Later, I just realized I was using 4.1. Updating R is the easiest and the fastest solution. Sorry for the inconvience.