It takes me awhile to figure out that i've a problem in my game .
I do street pick up a lot and have many numbers . But i never have date with any of them .

We exchange our number then i call her 2 days later . But the number is usually flake .
My pick up lasts 2 minutes on the street and then i get their number. Do you think that's the problem?

You need to talk to her longer if possible. She needs to feel a real connection if she's going to want to see you again. Unless you're really clear in your intent.

I'm not terribly clear in intent. So, the best results I have from numbers are the ones that I spend a long time getting to know. Sasha Daygame says you should be able to walk away and know five awesome things about the girl.

give this a shot man, here are some things

before even getting the number
-see how she responds to touch, if negatively, next her
-show interest in her and see if she will invest in a conversation and talk about herself past that point, if not, next her
-get her to agree to a date before you get her number, get the number as a result of her agreeing to hang out, if she won't, next her

^ this is screening, you will save yourself more time and emotional stress just simply walking away from these girls and finding others who screen better, it's easier to just open a different girl who screens better, then to text it up with some flake for 2 weeks only to find out it will never go anywhere and is a complete waste of your time and energy

after getting the number

-text her the day you get her number, have a little convo with her to get to know her better so that you don't have to go on a date with a complete stranger (you might not give a fuck about this, but alot of girls are not interested in meeting up with some random person they don't know), once you feel you actually know a bit about her, and there is a little common ground between strangers to the point where you are no longer strangers, just wrap shit up and keep the texting to a minimum past that point

-call her the day you planned to meet her for the date (don't text), and arrange where you're going to pick her up

-flakes will still happen even if you do everything you can to mitigate them, improve yourself, try to make more of an effort to make a connection with the girls you are talking with before you get their numbers and walk off, also, work on yourself, improve your looks/style/bodylanguage/grooming/hygene/confidence/demeanor/social skills

^ doing the above will cut back on flakes, and the amount of girls that you have to next through screening

-stay persistant you can keep contacting a girl as long as you want and ask her out infinity times until she stops speaking with you or tells you to stop contacting her, however if a girl flakes in a pattern of a good 3x or more, it's safe to assume she is unavailable to you sexually at the current time, and it would be a waste of time for you to put effort into her, put her on the back burner as less of a priority if you even keep her number at all

-you can also get girls to qualify themselves to dates, so they are slightly less likely to flake, you basically just get them to state they are sure they can make it for what ever reason (when a person says that they will exibit a certain behavior, they are more likely to exibit that behavior at least for a short period of time)

GOOD LUCK