Root How to indoor Samsung galaxy s3 mini

[stars_rainbows]

I have been searching hours on the internet and am now finally giving in and asking for help. I bought a Samsung galaxy s3 mini that has been jailbroken however I can't use some of my apps such as banking apps so I want to remove this and restore the phone to the factory settings. Super su is already installed but it keeps bringing up error message 'there is no su binary installed, and SuperSU cannot install it. This is a problem'...yeah tell me about it.

Any help will be greatly appreciated

Android version 4.1.2

Thanks in advance for all the help

 

[Jfalls63]

If you want to return it to 100% stock, you need to flash the stock firmware with Odin.
What is the complete model number, your country and carrier?