The plug-in failed and an error occurred after the player entered the server.

[User-Time]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:
An error will appear after the player joins the server.
（I don’t know if this has anything to do with me using a VPN?）

Expected behavior
No error is reported, the player's skin is replaced

Screenshots
If applicable, add screenshots to help explain your problem.

Version information (please complete the following information):

• Minecraft version: 1.20.4
• SkinFixer version: 1.7.9
• Operating system and OS version: Windows11
• Architecture: 64

Additional context
My "clash for windows" is in TUN mode

[TobiasDeBruijn]

Right. I think this issue stems from the API having some serious availability problems. I'll need to see if I can figure out a way for users to self-host the API, though I am very limited on time at the moment.
If you want to take a crack at it yourself, the API can be found here.