I dislike the notion of a district being 'lost'. It's more that they squish around.
When someone says that a specific district may be lost, I think it's misleading.
No one is going to suddenly not be in a district because their district was 'lost', they still have representatives in state legislature and congress same as before.
A state can lose districts and seats in the US House, but no specific district can be lost. The region and the people are still covered.
They may be covered by a district with a different shape and different boundaries that cut differently, but that is a normal thing that happens every ten years.
Things change, but nothing is ever 'lost'.