Can you go back to an old update version?

Hi iam on orange in the UK and updated my Q10 to the latest version which seems to have brought nothing but trouble with it. My phone was running perfectly before the update. Now I have lost all my text messages, my battery seems to not last as long and I've lost all my icloud contacts despite putting my password in the account settings correctly and my calander seems really slow.

I would really like my phone to go back to how it was, is this possible?

Please help anyone, thanks :)

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