They can be very picky about how they scratch. If the post is vertical try lying it on it's side. If it's carpet then the reverse side might be more appealing. Or a hunk of real wood with bark on might work.
I've had great success with the top 18 inches from an old cedar fence post. Cedar is fairly soft which they seem to like. I put it right beside or on top of where kitty is scratching now, play to get her putting her feet on it and leave it for a couple of weeks so she gets used to it. Then move it to a place more suitable if you must. Mine still lives in our living room and we vacuum up cedar shavings before company comes. Our cedar log has such a big scoop in it from successive cats sharpening on it that it may need to be replaced soon.