Filter condition not working

[ic57739]

Hi,

When I am trying to create ADSL based on training given in RStudioConf 2022 Clinical Reporting in R, I am getting error when I am running a piece of code to apply a filter condition not to keep subjects having values in ARMCD other than "A" or "P". The error is object 'ARMCD' not found.

Can you check what is the issue here?
My RStudio version in 4.3.1.

Regards,
Ishwar
adsl.txt
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