Try using a firming lotion.
Like dove firming or so...
The skin needs to be firm to your packs to be seen.
And take proper diet.
Taking junk food or food rich in fat/cholesterol can form a thin layer of fat that will cover your packs.
Ideally ,working out(25%) + proper diet (65%)+ firming skin(10%) is the key to a six pack.
Plus I think ur body might need resting time to recuperate from the exercises, maybe wrkng out every other day.