My hair dries puffy and the curls lack definiation

At night I shower then put in prodcuts (john masters leave-in, john masters gel, and Carols Daughter foam) I  plop for 20  minutes and then diffuse for 15. I then leave it in a bum to finsish drying overnight. When I take my hair out of the bun in the morning it looks great, but by the time i get to work my hair turns from great to puffy and some of the curls fall flat. Does anyway know why this is happening or what I could be doing wrong?Thanks