Why contactless payments can’t be expanded to Tilbury Riverside station

When contactless payments for travel across the southeast of England are expanded later this month, they can’t be extended to include Tilbury Riverside station, because it closed over 30 years ago.
It may sound odd to point that out, because of course they won’t work at a long since closed station, but there’s a very good reason for making the point. Although the station closed over 30 years ago, there’s still a “parliamentary” service calling at the station.