Scroll bug when opening webview / iframe in iOS and otherwise fine in android / web

I have a react app where I use material ui (older version).

please see the video where I have shown the bug.
video link (dropbox)

video showing behaviour in android device

Actually I am not getting any leads to find the bug, somehow it is just the problem happening in iOS when dialog box / popup opens and when the keyboard is opened. So when keyboard opens it just makes the whole page to scroll & that should not happen.

PS: please don’t mark the question as false as I cannot provide a reproducible code as I am not sure where the problem arrises (via material ui or common components or specific code), but if you find some bug and need some code please let me know in the comments and I ll update the question with that code. Currently I am not providing code as it works fine on web and android device.

What I expect: some IOS developer who might have come across the problem might be able to find the bug, it is somehow a behaviour of the iOS thing as it works well in android.