Pepsi have said occasionally the drinks may be coming out flat even after you have changed the gas bottles ,  here is what they have told us to do - 


  1. Turn the drinks apex machine off 
  2. go to the dispenser and press and hold the sparkling water button ( run into a cambro )
  3.  hold the button down till the water goes fizzy again - should see more bubbles and fizz.
  4. turn the dispenser back on in the back
  5. this should work and give you fizzy drinks again.