If you have installed an update NSP and the game fails to launch, consider the following:

Use the Switch’s built-in "Check for Corrupt Data" tool if the game crashes frequently after an update. Conclusion

An is the standard file format used for digital games, DLC, and updates on the Nintendo Switch eShop. When users discuss a "Terraria NSP update," they are usually referring to the installable update file that brings the base game up to the most recent version, such as Labor of Love (1.4.4). The Latest Major Milestone: Labor of Love (v1.4.4)