Also I followed feeding exactly as stated on back of the bag.
That's just the company's recommendation to sell more feed..marketing more than sense.
Many of us have found other feeding regimes to be better.
...and chickens don't read the bag, so may not lay/behave as cited there.
How are you lighting...time of light on and off..etc?
When did you start lighting....a week ago, a month ago?
Did this batch of chicks hatch at the same time of year?
Are they the same breeds from the same source as previous flocks?
Oh, and, Welcome to BYC!!
Where in this world are you located?
Climate is almost always a factor.
Please add your general geographical location to your profile.
It's easy to do, (laptop version shown), then it's always there!