have you deleted your contacts, messages accidentally?....
your lucky theres a sim card data recovery
it is a Software used for restoring accidentally deleted data from your sim..install it in your pc, connect it to your phone with unlocked sim
(usually they have PIN codes)...and it will retrieve everything.....
how?...well the explanation is quite the same as how data are recovered in personal computer..or in your rewritable cd
you know that your sim card has memory right....and your messages or contact are saved in your sim card...depending on your options
so the reason why you can still recover it is because the data is not totally deleted...if you accidentally deleted it in your phone...your phone simply tells the sim card that the data you had deleted, is the priority in deleting, in case the memory in your sim card is full...
so if your sim card memory is not yet full...or you havent save a lot of data after deleting it....then there is a big chance that you can recover it....using software
so your sim card is just like a used rewritable cd,being burned again...
if you put in too large data that it will need to delete the existing one it will do it...depending on your decision....anyway if you got more question just ask..
