I encountered this problem when I changed my Ubuntu One login email address to a new address and deleted my previous address.
The email address in Launchpad was not updated with the new address, so I was still receiving bug mail at my old address until I manually changed / removed the email address in Launchpad also.
I expected changes in Ubuntu1 SSO to be automatically applied to the associated Launchpad account.
I encountered this problem when I changed my Ubuntu One login email address to a new address and deleted my previous address.
The email address in Launchpad was not updated with the new address, so I was still receiving bug mail at my old address until I manually changed / removed the email address in Launchpad also.
I expected changes in Ubuntu1 SSO to be automatically applied to the associated Launchpad account.