Assign the same value if the condition is not met

I assume that if a certain condition is met then A = Y, but if it is not met A takes the previous value of A. But I have not achieved this.

seleccion: process (A, x1,x2,Y)
variable sel : std_logic_vector(1 downto 0);
begin 
sel :=  (x1 & x2);
if sel="xx" then
A<=Y;
else
A<=A;
end if;
end process seleccion;

thanks for your support.