Joplin Sync Source Upgrade Error

Joplin Version: 1.2.6.2479
Sync Version: 2
Profile Version: 34
Platform: Windows 10

What I was doing when error occurred:

I opened Joplin for the first time in a while and got a prompt to upgrade the sync target. I let the program do its thing and it failed with the following:

Error
The sync target could not be upgraded due to an error. For support, please copy the complete content of this page and paste it in the forum: https://discourse.joplinapp.org/

PUT locks/exclusive_desktop_1f6bf3b1d0174537b7e07e964a988845.json: Unknown error 2 (429):

Error: PUT locks/exclusive_desktop_1f6bf3b1d0174537b7e07e964a988845.json: Unknown error 2 (429):
at newError (C:\Program Files\Joplin\resources\app.asar\lib\WebDavApi.js:399:11)
at WebDavApi.exec (C:\Program Files\Joplin\resources\app.asar\lib\WebDavApi.js:429:10)
at async FileApiDriverWebDav.put (C:\Program Files\Joplin\resources\app.asar\lib\file-api-driver-webdav.js:201:10)
at async tryAndRepeat (C:\Program Files\Joplin\resources\app.asar\lib\file-api.js:38:19)

Actions attempted:

Upgrading the latest version of Joplin fails to sync with the error below:

Completed: 30/11/2020 14:22

Last error: Error: PUT locks/sync_desktop_1f6bf3b1d0174537b7e07e964a988845.json: Unknown error 2 (429):

Did you figure out how to fix this by chaance? It's been making Joplin useless for me.

The above error was due to a misconfigured WebDAV server. If you're having a problem with sync, please create a new post and provide details.