A pre-order will remain on hold until 60 days after the game or DLC is released, after which it will be cancelled. If resolved, the pre-order will be restored, and the game will be purchased within 7 days of its release.
A Nintendo eShop pre-order will be pending, or placed on hold, if the Nintendo Account that placed the pre-order deactivates all Nintendo Switch systems it has been associated with.
What to do
To restore the pre-order, link the Nintendo Account that placed the pre-order to a Nintendo Switch system, if it is not already linked.
From the Nintendo Switch HOME Menu, open the Nintendo eShop and select the Nintendo Account that placed the pre-order. The pre-order will be reinstated when the Nintendo eShop is opened.
To verify the status of your pre-order, select your user icon in the top-right corner of the Nintendo eShop and scroll down to Your Pre-Orders to view all open pre-orders.