Thank you for your reply, Harald!
Sorry I forgot to write the basic information.
I use the following version:
Spine 3.8.97
Unity 2019.4.2f1
runtime : spine-unity-3.8-2020-05-25
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When did this error occur?
I had added some new skins to the skeleton, and the error occurred when I played a game scene in Unity.
Does it occur when you import the assets into the Unity project (drag the files into the Assets folder)?
No, it doesn't.
Honestly, we modified the skeleton for making it easy to update, so the skeleton is not used with only Spine-Unity runtime. It is using our original script that divides the skeleton of each skin.
I think it might not get supported since the reason, but I can't solve it myself.
FYI, if the skeleton was just put with Spine-Unity runtime, it is working.
Does this error only occur at a single skeleton, or at multiple of your assets?
The error only occur at a single skeleton.
Sending the problematic package
Ummmm... It is difficult because I can't share the error without the big game package.
I'd like to know what the reasons will be cause the error, even if the reasons are just part of possibility.
