I upgraded both Home assistant app version and the OS - I don’t remember the exact sequence but now I can’t access home assistant - it’s stuck on loading data. I’ve tried different devices, clearing cache of the internet browser, restarted the raspberry but no luck. I’m not very technical - any pointers on what to do or how to restore a backup…
On the occasions that this happens to me I have to physically reboot (turn off the hardware device HA is running on, then turn it back on). This usually seems to resolve hang ups for me.