For those who don't want to waste their time, just follow these steps. https://stackoverflow.com/questions/73313352/app-store-screenshots-screenshot-uploads-in-progress-error-appscreenshotse
after 7 days without getting any support from apple i solved it with the steps given in the stackoverflow link
ycdaskin
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i am facing this issue for 2 days. it is really unbelievable that the same bug is not solved in 2 years. all i can do is just to wait? will the problem be solved by itself?