Without a subscription or in-app purchase of premium services there will be nothing stored in the cloud. Normally everything is downloaded automatically after installing the Lightroom app on a new phone. In your case the images will be stored internally on the old phone within the app system location. If the Samsung Smart app is unable to transfer the files I don’t know of any other method. In any case it’s not a great method for installing apps. I would suggest uninstalling and getting the app as a fresh download from Google Play. But I fear you will need to load the photos manually if you wish to continue with the free mobile version. Alternatively use the old phone as an archive and the new phone for any new photos shot going forward, albeit not great for sharing without a SIM.