I used to get "wpi 858" printed in black on the tablet of Bupropion SR 100mg tablet. Now I am getting exactly the same size and color pill except that "wpi 858" is not printed in black but is only imprinted(the tablet does not have black writing but only has an imprint of the same writing). These new pills taste very bitter and don't smell as bad the the ones with black print. But it also appears that they are less effective. What is going on? How can I get my original pill?