can't add a custom seed - minecraft xbox one v1.9.0

Issue

i cannot create a world in minecraft on xbox one with a seed of my choosing.

Steps to replicate

1. Load and login to minecraft on xbox one (UK)

2. verify version is "v1.9.0" as displayed in the bottom right of the screen

3. click the "create new" button

4. click the "create new world" button

5. in the "edit settings" > "game" > "seed" setting, enter a custom seed.

6. click "create"

7. load the menu

8. verify the seed is different than the seed that was entered in stage 5