Hello,
I do not know SASHELP.VCOLUMN very well.
Instead I always use PROC SQL with the dictionary.columns dataset.
But SASHELP.VCOLUMN is a view on this dictionary.columns dataset (the latter you can only access via PROC SQL).
In dictionary.columns the libname and memname column are all in uppercase.
Therefore, I would recommend you try uppercase notation :
where libname='WORK' and memname in ('C2020','C2021');
instead of
where libname='WORK' and memname in ('c2020' 'c2021');
Probably that is the solution to your problem.
Thanks,
Koen