Lightroom mobile issue

Hi, I wonder if anyone can help please? I downloaded Lightroom onto my Iphone a while back. I've now bought the photographer bundle (I think thats what its called) with the 20GB storage. I had deleted the lightroom on my phone and used the link via the creative cloud to download, but I've realised my phone recognises the app from before and won't recognise the premium setting only free. I've tried to permanently delete the app and try again but there doesn't seem to be a way to do this as Itunes have moved away from managing apps in its software. Is there a way to change it to premium via the Lightroom app? Or a way to permanently delete it and start again? I've tried syncing but that didn't work either. Thanks. Gina