Unlocking iphone 5s

[Anonymous]

I wanna unlock my 5s cuz I am gonna work abroad soon.
I phoned them, twitted them and live chat with them. All of O2 staff said I can unlock it once I pay off my phone plan.
But on official website it says: except the 5c & 5S which can't be unlocked.
So my question is: who's information is correct? Can I unlock my 5s immediately if I pay my phone plan?

Cheers

[Anonymous]

Hi

It shouldn't lock but I would use a different carrier sim first before inserting O2 sim again lol

[MI5]

Once unlocked properly it stays unlocked forever.

[Anonymous]

i put O2 sim card back to my phone.
no 4G signal at all. I've trid to reset network, reset phone, reset network setting.but still can not use 4G

but when I put other carriers, 4G works fine...

ahhhhhhhh 

[MI5]

It's because you don't have the latest O2 carrier update.

[Anonymous]

Are you sure the signal is not down in your area at the moment

[Anonymous]

 i did update carrier setting as well

[Anonymous]

yes my husband's 4G O2 network works fine

[MI5]

Can you try husbands sim in your phone?

[Anonymous]

nop he got samsung, my is iphone 5s. even Enable 4G is on, but only can see 3G or sometimes it shows 1 bar signal

[MI5]

Try a new sim in your phone.