why every time I fill up 2001 Kia optima won't start?

[al azhr misbah]

2001 Kia Optima V6 auto, the car start runs and drives very good until I fill it up gas ( regaler ) and it happens every single time, after I put gas in the car it won't start, and it turns on but after trying 5 to 6 times and when it starts the engine shacks for like a minute, but runs good after, I never heard of something like this before, please if you know what might cause that to let me know.
like I said the car won't start right way only when I put gas in it.
thank you.