iMovie on iPhone 13 freezes after asking for permission to access photos and music

I have used iMovie on my iPhone 13 before with no problems. Perhaps some bug was introduced in iOS 18.1.1. When I launch iMovie, the first thing it now asksme is for permission to access my photo library and music. As soon as I tap on [Continue], the app freezes completely. I have force-restarted my iPhone, but it doesn't help. iMovie freezes at the same place every time.