I think the individual should do some analysis of their lives and try work up from there
Is it very baseline things that are causing anlack of flow factor; are your basic needs being met for example?
If all good then I would then move onto basic beliefs, what do you think about yourself, other people, is your standing in society a neutral one or is it skewed?
Then try see if your parents have some hold on you; do you still seek their validation? Still want them to subconsciously make decisions for you about what to believe?
And keep going until you find a common factor that is causing any hold ups.
A big one for me is nutrition and more water. Also including more excercise into my schedule too. This is helping me in a big way.