Commit Status Publisher (VSTS) throwing a 400 error

Hello,

I recently updated my TeamCity version to 2017.1.3 (build 46961). One of the reasons to update was to have access to the Commit Status Publisher for Visual Studio Team Services. Upon updating, I realized it still had to be enabled, so I went and enabled it in the internals, and set everything up as I should.

I created a token and all that, and now I want my commits that are the result of a merge on a Pull Request to be evaluated. The builds are being triggered correctly, but I am getting errors on the commit publisher.

The worst part is the errors aren't even understandable. Sample of the log with identifying info removed:

2017-08-04 14:44:55,764] INFO - tbrains.buildServer.ACTIVITIES - Finished build z:: Build {id=z_Build, internal id=bt9} #39 {build id=1023, promotion id=1023, branch=575/merge, history=false, agent="x" {id=1}, triggered by "Git" (##vcsName='jetbrains.git' type='vcs'). Started 2017-08-04 14:33:08.010, running}

[2017-08-04 14:44:56,318] WARN - HttpBasedCommitStatusPublisher - Commit Status Publisher HTTP request has failed. Publisher: tfs(https://y.visualstudio.com/_apis/git/repositories/OmniaPlatform/commits/ce8181af3a6b13f4cf07(...)/statuses?api-version=2.1).. Build: #39 {build id=1023, buildTypeId=OmniaPlatform_Build}: jetbrains.buildServer.commitPublisher.HttpPublisherException: HTTP response error, response code: 400, reason: Bad Request (enable debug to see stacktrace)

How should I proceed? I understand this is a pre-release feature, but I'd like to understand what is happening.