My 16 gb memory card not working...

Hello,

i have this 16 gb sandisk memory card with lots of files of mine stored in it.i had been using it for only 2 months untill now.bow everytime i plug it in my pc it tells me to format the card.when i go in settings in my phone it tells that the memorycard has an unrecognised format that needs to be formatted and it says that i shall reformat the card but i dont wannna lose my data .last time it happened i changed my card and had a lot of difficulty in getting my data.(actually some of it i had it in my comp.)this time id ont wanna lose nothing.please help me sir/madam.PLEASEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE :((