4 digits 7 segments blinking problem

i use 5461bs 4 digit 7 seg module. i can display on each of the 4 digit , but i am having problem when i want to use all of them one after the other in order to get 4 digits number display.
i get blinking display of the digits instead of stable one as expected , even that the delay is: delay(2);
how can i get it work without blinking?

my code is attached.

four_7seg.ino (3.77 KB)

Wiring diagram?

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Note particularly point 7.

Define "blinking". Or better yet, post a video.

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