1. When logged in as admin in the backoffice, navigate to 'Products'.
2. Select the product you want to change its market.
3. Click the 'Edit' button next to the product you want to change.
4. Select the 'Variants' tab.
5. In the 'Available in' field under 'Selected Variants' section, add the market you want to change to.
6. Select 'Toyko' in the list.
7. Remove the market you do not want to make the product available to, in this case, Singapore.
8. Click 'Save' after the changes.
9. Click the 'Publishing' tab.
10. Under 'Publishing Rules', add the same market that was added to the variants in 5.
11. Select 'Tokyo' in this case.
12. Click 'Save'. If this product needs to be published, click the 'Publish' button at the top right of the page.