mobile phone help

[kieras nana]

hi,
hope someone can help.i bought my grandaughter,a mobile phone & within 2 weeks,it kept turning itself off.she was on holiday,at this point,so when we managed to take it back,to the shop,it was 3 days passed,the 28 day,return policy,so they wouldn't give her a new one,they just sent it off,for repair.
anyway,she got it back yesterday & she has just phoned me,to say it is exactly the same.
we bought it from,an orange shop & it cost £70,now i know,this isn't top of the range,but she is only 8,so this was what i was willing to spend,but even for £70,i expect it to last,longer than 2 weeks.
i wasn't happy,at it being sent off for repair,as there was obviously,something wrong with it,but i accepted it.
can someone please advise me,if we can expect it,to be replaced,with a new one,as this is what i would prefer,but i would like to know my rights,before i go back to the shop.
hope someone can help,
tracy

 

[Disney Princess Elli]

is it a sony ericsson?
they're famous for just randomly turning off by themselves, often when you're trying to do something important.
and i know people who get them fixed but that never works as there must be a fault with sony ericsson's hardrive thing they put in phones..

 

[kieras nana]

it's an LG one,where a keyboard slides,out of the side of it.
not sure of the exact model.
tracy