amiibo-compatible games are separated into two types: "read/write" and "read". Games that use the read/write functionality of amiibo can both save and read data to and from an amiibo. Games that use the read functionality of amiibo only read data from an amiibo.
If you use an amiibo with a game that uses the read/write functionality, for instance Super Smash Bros. for Wii U, you can still use the same amiibo in other games that use only the read functionality, such as Super Mario Maker on Wii U.
However, a single amiibo can only be used with one game that uses the read/write functionality at a time. To use a different game that uses the read/write functionality with the same amiibo, the data must first be cleared from the amiibo using "Delete Game Data" in Nintendo Switch System Settings, “amiibo Settings” in Wii U System Settings, or in HOME Menu Settings on Nintendo 3DS family systems.