Incoming text problems-UK

[samlr]

I am on orange and since having my s3, I have had problems with receiving text messages from certain people (3 that I know of). Its not a presistent problem, I can be in a middle of a text convo and then wont receive their reply or just someone texting on the off chance and I dont get it! When I say I dont receive them, I dont mean I then it get it hours later, I dont receive them at all!! Its really frustrating especially when someone calls me and tell I find out they have sent me 3 texts that day and Ive not received any of them! Orange have been no help at all! Has anyone else had this problem?