My b2evolution Version: Not Entered

I tried to log in to my blog as admin, and the old password suddenly does not work. I did not make any password changes.

I clicked on the "forgot password" and followed the link that was emailed to me, but it didn't work either. It says "You have to use the same session (by means of your session cookie) as when you have requested the action. Please try again... "

I'm locked out. Please help.