Videos are not autoplaying with sound in IOS

Hi devs,
I’m on the way to developing an application which shows 2 to 3 videos on the onboarding flow. I want the user to unmute the very first video and then all upcoming videos should autoplay with sound on the IOS(Safari).

I tried some solutions using Javascript but failed. Can anyone suggest an approach or solution to solve this is highly appreciated.

Thank you.
My application link: