Excel returning a False response

=IF(B12<>"",(IF(U12="Subscription","Subscribe",IF(U12="T.E.H.","Subscribe",IF(U12="ESA","Subscribe",IF(U12="Perpetual","Buy",IF(U12=" "," ")))))))

I get a "False" value in the cell with this formula in it when the value in U12 is not one of the options and I want to get a blank Appreciate any help Thanks