Mobile chat (full screen) overlapping app switcher on iPhone

I have a webview mobile app which has my website embedded in it. I have the Tawkto chat in there, but when the chat opens on mobile, it goes full screen inside the webview which causes the "type here and press enter" input to overlap the bottom of the screen (below the iPhones natural viewport, near the home/app switcher toggle). Then, it's hard to click the bottom items on mobile because it always wants to open the app switcher / home toggle.