Why can't I reach Route 19 and 20 in White 2?

Question

I have completed the elite 4. But I still cant get to the islands on the southwest part of the map. The islands dont show on my map. I also cant get to clay tunnel in driftveil city. It is really strange but I dont see a way to get to these places. Does anyone know why this is?
I dont know but maybe it has something to do with that I caught zekrom in the castle. Because I also dont have the dna splicers. I dont know why.

Answer 1

You're playing the wrong game. In the image that you commented I noticed that Route 10 was present, as it is in only Black/White. Route 10 was "destroyed by a landslide" in Black 2/White 2, which is why it is not present in those games. Route 19 and Route 20 didn't exist in the events of Black/White, so it's impossible to get there. You'll need to obtain a copy of Black 2/White 2 to be able to traverse those 2 routes.

Source: Your image

Answer 2

You say you have beat the Elite Four, meaning you have already passed both of those routes. Route 19 is where the catching tutorial is, and Rroute 20 is blocked until you get the Basic Badge, but is west to Virbank City.

https://bulbapedia.bulbagarden.net/wiki/Unova_Route_19
https://bulbapedia.bulbagarden.net/wiki/Unova_Route_20

Oh, I see. You are actually playing White, not White 2. Routes 19 and 20 did not exist in White, and neither did Clay Tunnel.

Comments

I have never passed these places. https://s.amsu.ng/zXoxi9SX5M6N
In the image you can see that i have never passed these places.