For them talking on the phone is like hitting the pool hall.
But waiting for too long will create the impression that you are not a serious guy. Just imagine calling and having to struggle to let her know who you are. Know why you are calling You must always have a reason for calling. Let it be brief You call to find out something; that should be it.
Although women love talking on the phone, they want to do that with friends.
If your boyfriend doesn’t call you back it’s likely because he expects you to make the effort to make the call.
It shows him that you’re not craving to talk to him and it also shows him that you have better things to do with your time than pursue him.