"No Conference found with key: " + websafeConferenceKey));
}
// Un-registering from the Conference.
Profile profile = getProfileFromUser(user, userId);
if (profile.getConferenceKeysToAttend().contains(websafeConferenceKey)) {
profile.unregisterFromConference(websafeConferenceKey);
conference.giveBackSeats(1);
ofy().save().entities(profile, conference).now();
return new TxResult<>(true);
} else {
return new TxResult<>(false);