The puzzle generator in the game requires a word that is at least 3 letters long in order to create a puzzle. (For more information, see: Why can't I create a puzzle with my amiibo?)
However, some words that are considered long enough can still not be turned into solvable puzzles. For instance, a Word Maze containing only the name "BOB" would be unsolvable, and it is impossible to create a One Word puzzle that contains "EEVEE" only once, when it is hidden among the letters "E" and "V".
These are extreme examples, and other words can cause issues with puzzle generation too. Word Maze and One Word puzzles may not always be possible using the data stored on your amiibo.
Mixups puzzles, however, can be generated using any word containing three or more letters. When it is not possible to generate grid-type puzzles, there is always the option of a Mixups game. As a consequence, some amiibo are only able to produce Mixups puzzles.
Please contact us with the name of your amiibo and its owner if you would like further explanation.