WordPress does not acknowledge my username anymore?

Hi, i havent been logging in to my wordpress admin in my blog for almost a year. apparently wordpress kept on prompting “invalid username” when i tried to login. will wordpress delete my username if its no longer active for quite a while? one more thing who should i check with if my website is “not found”. does this mean everything that i had earlier in it are all gone? any advise is greatly appreciated. thank you;)