Sorry to say you did not win a Samsung S9 phone from Mozilla. This is '''100% FAKE''' and was not a message from Mozilla or the Firefox web browser. '''Do not give them any personal information or send them any money by any means.''' Variations of this sort of scam has existed for a long time, not for Firefox users but in general. Mozilla does not do any so called surveys with claims that you have won or will receive insert expensive prizes as the three main variations have been for a iPhone X, a $1000 gift card or a Samsung S8 or S9. Mozilla has done surveys over the years by way of http://qsurvey.mozilla.com which is surveygizmo.com however no prizes are given. Below are a few examples of the iPhone X for a $1 Scam version I have seen in last while as the variations of this scam for $1000 gift card and Samsung S8/S9 were describe in similar fashion.