If/else

I have an if/else statement here that when it comes off the 50th frame, a button is supposed to become fully opaque. This isn't working:if (glam_mc._currentframe == 50 ){ glam_mc.next_btn._alpha = 25; }else if (glam_mc._currentframe <= 49){ glam_mc.next_btn._alpha = 100; }Can anybody point me in the right direction? I thought this should work?Thanks in advance...!