Failure to update software

[TR20]

My A30s sumsung phone keep say " your phone's operating system has been modified in unauthorized way" when I'm trying to update the software,  what could be the problem  and how can that problem get fixed please?

[Moaizam]

Try again after reboot .
Otherwise last option is that , first erase your phone then again setup.

[MLK_ZBR]

Hard Reset is the only safe option

[NabeelAhmad]

You need to flash official firmware first.
If your phone is genuine and not refurbished, then do. otherwise keep using without update.
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