Bitstamp GPG key difference

[tok]

I am trying to reset my two-factor at Bitstamp and sent an email to support@bitstamp.net

I received a reply from support@bitstamp.net that they require a scan of my id for that.
In the same email they request to optionally encrypt the mail using attached PGP key with ID: 4E90C8A0

However when I search for support@bitstamp.net I get another keyID: 469D6D44 see http://pgp.mit.edu/pks/lookup?search=support%40bitstamp.net&op=index

Anyone know what's going on here?