stolen phone

If you only had the free Lightroom app, then you will only be able to retrieve the images IF you had taken a recent backup of the phone (such as iCloud if it was an iPhone). The free Lightroom app only stores images on the phone, they are not synced and backed up to the Adobe Cloud, and it's the users responsibility to maintain suitable backups.

If, on the other hand, you had an Adobe subscription then your images should all have been backed up to the cloud, and can be accessed from any device provided you have installed the appropraite Lightroom app and logged in using your Adobe subscription details..