@QYM In general please always provide as much information as possible, with just the information provided above we can't help.

Which exact version (name of the unitypackage, also listed in Assets/Spine/version.txt, or version in the Package Manager) of the spine-unity runtime are you using?
What render pipeline are you using in Unity? Built-In RP, URP 2D or URP 3D?
Did you see any warnings or errors displayed in the Console or in the SkeletonAnimation component?
Which skelton component are you using, SkeletonAnimation, SkeletonMecanim or SkeletonGraphic?
Could you share screenshots of the component settings, including the Advanced section?
Could you show a screenshot of what your skeleton looks like in the Spine Editor and in Unity?
Could you show screenshots of the Materials at the Skeleton?