Gamin Edge 520

it records the rides ok when I go out ridding but when  I plug in the wire to the back of it and the other end of it into the usb port on the computer 

so that I can send the data to Stava to show my friends (encourage each other)

Garmin Express asks for my email address & password both of which I enter only to be told the password is wrong!

so I click on the forgotten password and am send a temporary password so that I can mark a new one,

all is fine until the next time I want to  send the data to Stava.

please can someone help me-Ian