The London Sleep Centre’s advice for new parents:
Newborns have no sense of night and day. They learn this from the behaviour of human beings around them. It is quite normal at the beginning of life to have a chaotic sleep pattern.
For the first six months, babies will fall asleep pretty much anywhere, any time. They gradually begin to become more aware of their surroundings and begin to develop a routine.
The best way to settle your child is to put them in their cot at a time you have noticed is a common time for them to fall asleep (this could be 9pm or later and won’t necessarily be at 7pm).