Using iconv code map in shinyapps.io

I was trying to convert EBCDIC to ASCII using iconv with base code as IBM037. This worked fine in my local windows10 machine with R 3.5.2. But its not working on shinyapps.io
Is it that code file not in shinyapps.io ? Is there any way to solve this ?
This is the code snippet
xyz <- iconv(mydata,from="IBM037")