I'm just making sure you're using the Quest 2 version of HereSphere, which you downloaded from itch.io. There's a PC version of HereSphere available on Steam, which would require different steps to reinstall the app.
I'd recommend uninstalling HereSphere. You can do this by pressing the icon that looks like 3 dots next to the app. Then try to install the app again, and see if it works.