iMovie project frozen on iPhone

My iMovie project is frozen on my new iPhone 16 Pro Max and I cannot complete editing it. I did the basic troubleshooting - latest iMovie version, rebooted the phone (many times), closed and reopened the app, checked storage space (931 GB available). I’m at iOS 18.1.1 - but I’m seeing people get MORE issues with iMovie getting frozen after the latest 18.2 update, so I haven’t done that yet. I contacted Apple Support and they asked me to call back into the specialized English customer apps desk since they couldn’t help. I haven’t done that yet - I thought I may have better luck across the whole Apple community!