Hello, The problem with your geometry is that you have an uneven amount of axis subdivisions in the original cylinder (if my counting is correct) -25 - you need an even number like 24. It's probably better to start again. Then I would use the poke command on the centre face and delete every other edge it creates so you get quads in the centre (see image). This should help when you smooth the model. Hope that helps! It does, thanks.