I tried to follow the new Blender 2.8 tutorial from Blender Guru. https://www.youtube.com/watch?v=6OTX3ZdYvEA
Alt + H in Edit Mode before apply modifier and you can solve this problem.
We're looking for long answers that provide some explanation and context. Don't just give a one-line answer; explain why your answer is right, ideally with citations. Answers that don't include explanations may be removed.
(Assuming Blender 2.80) It looks like you are using the bevel modifier and the subdivision modifier. Switch both (first becomes second and vice versa)