You're not giving us much to work  with!
I take it that CalcSheetv2 and NEWSELBilling
are objects that you've defined as Workbook objects?
It looks like you're trying to copy  a range  of cells
(B31 thru Q31) from the FIRST worksheet of one
workbook to the last row (in column "L") of another workbook.

Are both workbooks open?

I need to do some testing, but I THINK that you're combining
two different copy methods.
One is used to copy Filesystem objects, another would be used to
copy ranges.

Have you tried recording a macro to do this and look at the result?


Can you provide a bit more of the macro that precedes this snippet?