Update iOS

See what I wrote above. It's not possible to install the version you downloaded; you need to delete it.

James: No iOS device has a maximum OS version of 12.2. The only difference knowing that would make is finding out which version Inatsha should be seeing; the steps involved in fixing the issue will be the same.

(183535)

It's no longer possible to install that version. Open Settings, General, and Manage Storage, delete it, and check for updates again; you may need to remove the beta profile from the iPhone.

(183532)

Also before you update, switch off Low Power Mode.

which device?