Call forwarding to an unknown number already in phone

[Anonymous]

I got a new Xperia Z3 Compact just over a month ago on o2. I've just had a look at my settings for call forwarding, and for the options 'Forward when busy', 'Forward when unanswered' and 'Forward when unreachable' there's a phone number already set to forward to which I don't recognise. It's a full +44 one. I've searched all my contacts (haven't added or deleted any recently) and given the number a Google and a search in Truecaller to see if it's a known scammer or anything, but nothing has come back.

I can't seem to change the number as it gives me the message 'Unexpected response from network' when I try, although I can set each option to 'disabled' for the moment.

I'm obviously a bit nervous about giving the number a ring, and a bit paranoid as to why the number is there in the first place. Would anyone be able to shed some light on how it might have ended up there?

[Anonymous]

Thanks for the answer mate

[Anonymous]

I have an app or what Called Users and there is a phone that was not my own. It seems to have taken over my phone. I have deleted it but I've just asked for advice from 02, and I used my correct number, I had to type in my name then number but 02 keep saying my real number is not recognised.

[Anonymous]

Also, someone else appeared too.take over my keyboard this afternoon, I was texting but so was someone else! That started my voyage of discovery where I read that someone else can use your phone independent if me. I have uninstalled so many apps, that I did not verify or install. It is really scary. I was wondering why my phone bills were so high. What can I do?

[MI5]

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@Anonymous wrote:
I have an app or what Called Users and there is a phone that was not my own: 07849446308? It seems to have taken over my phone. I have deleted it but I've just asked for advice from 02, and I used my correct number, I had to type in my name then number but 02 keep saying my real number is not recognised.

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Link to app please?

[Anonymous]

Please remove your number from the thread as you aren't allowed personal info displayed & you don't want to get people spamming you

[perksie]

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@Anonymous wrote:
Please remove your number from the thread as you aren't allowed personal info displayed & you don't want to get people spamming you

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That seems to be the problem, it's not his number. 

[Anonymous]

Has some sort of virus got into the OS?

[jonsie]

Try a full factory reset and only add the apps you can verify. Make sure you back up your contacts and photos first. Also check your phone settings and make sure that automatic restore is unpicked in Backup & Reset

[Bambino]

Make sure you go into Settings>Security and ensure Unknown Sources is off. You can only install apps from the Play Store that way.

[MI5]

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@Bambino wrote:

Make sure you go into Settings>Security and ensure Unknown Sources is off. You can only install apps from the Play Store that way.

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That is usually off by default so would have to be turned on manually to install an app in this way.