UIKit Javascript : Fileviewer Header width overflows and not scrollable

“sendbird”: “^3.0.148”,
“sendbird-uikit”: “^2.2.1,

I’m developing WebApp using React, Cordova

When I click images attached in a chat, file viewer appears.
In normal browser, it looks fine, but in mobile view (which has width less than 500px), File Viewer header overflows so the “close” button is not visible.
[normal browser view]
[phone view]

How can I fit the file viewer header into window size?