login problems

I am having problems logging in to get akismet set up on my blog. I am a wordpress.org customer. I am asked to login which i do using my usermname and password I use to access my dashboard and write posts etc however this is information is not being accepted. When i then click on lost password I am asked to type in my email address. i type in the email address i use for my blob and I am then told that there is nobody registered with wordpress with this email address. I have never used anyother email addres or login information with wordpress except for the login details i just created to access this forum. I have tried using this information too but with no avail. can anyone help as i am so confused and frustrated! Thjis is also preventing me from getting any support directly from wordpress and from upgrading my blog software.
thanks