You can only import data into the same version that exported it. Sometimes JSON data from other versions can be accepted, but it is not guaranteed or supported. Binary data from a different version is very unlikely to be accepted. You should use your Spine project file instead, which can be opened by any newer versions.
You can set your version back to an older version in the settings:
Settings - Spine User Guide: Version
You can import the data in that older version, save a Spine project file, then open that in newer Spine versions.