The issue you're experiencing with the "Could not automatically set the AtlasAsset" error in Unity when exporting sequence images from Spine is likely related to the export settings, particularly the file extension used for the atlas. Ensure that the atlas is exported with the correct extension, .atlas.txt, as Unity requires this specific format to recognize the atlas file properly. If the problem persists, it might be helpful to check if there are any missing regions or incorrect paths in your atlas file, as these can also cause import issues. Additionally, ensure that your Unity and Spine versions are compatible and that you are using the latest spine-unity runtime package.

@megametx Sorry to hear you're having troubles.

the problem persist whenever I export sequences image to unity, uncheck the sequences and it wont have any problem

I assume you mean the problem occurs whenever you're exporting and having any Attachment set to Sequence in your skeleton, is this correct?

This sounds as if your spine-unity runtime does not match your exported asset version.
Which versions of the Spine Editor are you exporting from?
What is the exact version of your spine-unity runtime (name of the unitypackage, also listed in Assets/Spine/version.txt or in the Package Manager)?

Sorry for the late reply. This is covered in this enhancement issue ticket, permitting trailing space for sequence attachments:
EsotericSoftware/spine-editor813