R and ifelse function

I'm stuck in a simple problem argument with the ifelse function in R. I'm a new user of R and I'm trying to fill blanks in a column ("first column") depending on values in another column ("second column").

As I try ifelse function, I'm getting this error "argument "no" is missing, with no default"

All I need is: if the test (condiction) is FALSE, keep the values (from a factor variable) in the "first column" as they are.

Thanks in advance.