That unit looks like it only has UK & Ireland maps. Garmin DriveSmart 55 MT-S UK?? Unless the unit was purchased with Europe maps?? You won't be able to get them through Garmin Express unless purchased from Garmin. Cutting off at Normandy is because the UK&Ireland map tiles extend to that extent to include the channel isles.
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My Garmin 390Lm has all of Europe like Redboots unit yours specifies UK and Ireland. You can install (free) garminised Open Street maps to an SD card in your Unit to extend its capabilities outside the British Isles.