Greg Davies

Make sure your Nintendo Network ID is linked to the Nintendo account your using on the Switch. You can learn more about linking a Nintendo Network ID with your Nintendo account by visiting Nintendo’s official page here – http://en-americas-support.nintendo.com/app/answers/detail/a_id/15990/~/how-to-link-or-unlink-a-nintendo-network-id-to-a-nintendo-account

After you link your account you can access eShop funds across the all Nintendo platforms, Switch, Wii U & 3DS.