It seems Blue Yonder are chaging users passwords if they are not strong passwords.
This means they have to be longer than 6 characters, contain upper and lowercase letters and at least 1 number
By resetting all passwords which are not strong, this forces you to arrange for your password to be reset, or by using your main account details, change your password in Blue Yonder SelfCare
To change Blue Yonder and Virgin Media email accounts use their selfcare ==> CLICK HERE
You may have to enter your account email address e.g. email@example.com and password not your normal email address