When you want to
make a raise, you should not say, "I call your bet and raise you XYZ." Your
initial action is considered your final action. So if you say, "I call ..." it
means you just want to call. If you want to raise, say "raise" and state the
amount you want to raise, if it is a no-limit game (the amount of the raise is
obvious in fixed-limit games).
