Hi team, i'm pretty new to your software but i'm having a really annoying problem. i recently got the new lightroom and was really enjoying using it with lightroom mobile. then a few weeks ago i got a notification on my PC saying i couldn't use the same catalogue and i had to start a new one. now the phone app doesn't is one the old catalogue and my PC is using the new one.
You add your images to the new catalog on your PC and sync your files from PC to Mobile Application, also you can add some images from the gallery to Lightroom Mobile app and sync it to the PC catalog.
Whenever you change the catalog on your PC and you sign in to Lightroom mobile to sync, then it will prompt you to delete and switch catalog on your Lightroom mobile device.
You can sync one catalog to Lightroom mobile at a time.