C4 is backwards.
You don't say if the 555s are ordinary "high" current ones or Cmos ones that draw nearly no supply durrent.
You don't say if the U3 buzzer is a high current mechanical one or a low power piezo one.
The U3 buzzer messes up the input signal to the second 555. Connect U3 to pin 3 of the first 555 instead.
I am glad you re-connected the buzzer to the proper position.
Didn't you look?
The datasheet for the NE555 shows its supply current is 5.5mA with a 9V supply. So two have a supply current of um, duh, 11mA. That is the "typical". The current might be more or less.
The operating current of the buzzer and the LED must be added.
I have always made sure pin 4 on a 555 is never left floating, if your are using a 'buzzer' as in self interupting vibrator you are going to have big problems.