I have this plugin enabled for a project. During the build, it generates this error:

Started by user — -----
Notifying endpoint 'HTTP:http://localhost:9090/hubot/jenkins'
Building in workspace /var/lib/jenkins/workspace/XXX
> git rev-parse --is-inside-work-tree # timeout=10
Fetching changes from the remote Git repository
> git config remote.origin.url git@github.com:XXX/XXX.git # timeout=10
Fetching upstream changes from git@github.com:XXX/XXX.git
> git --version # timeout=10
> git fetch --tags --progress git@github.com:XXX/XXX.git +refs/heads/:refs/remotes/origin/
> git rev-parse refs/remotes/origin/master^

{commit} # timeout=10
> git rev-parse refs/remotes/origin/origin/master^{commit}

# timeout=10
Checking out Revision f2032e23549d962696fc976ce85fd77aee940f80 (refs/remotes/origin/master)
> git config core.sparsecheckout # timeout=10
> git checkout -f f2032e23549d962696fc976ce85fd77aee940f80
> git rev-list f2032e23549d962696fc976ce85fd77aee940f80 # timeout=10
[XXX] $ /bin/sh -xe /tmp/hudson1170039673840754778.sh
+ npm install
npm WARN package.json XXX@1.0.0 No repository field.
Archiving artifacts
Notifying endpoint 'HTTP:http://localhost:9090/hubot/jenkins'
ERROR: Failed to notify endpoint 'HTTP:http://localhost:9090/hubot/jenkins'
java.lang.RuntimeException: Adding artifacts mapping 'index.js/archive/http://jnx.lifeplansdev.com/job/XXX/9/artifact/lib/api/api/v1/index.js' - artifacts Map already contains mapping of location 'archive': {Gruntfile.js=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/Gruntfile.js}

, development.json=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/config/development.json}

, config.json=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/config/config.json}

, production.json=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/config/production.json}

, knexfile.js=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/knexfile.js}

, index.js={archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/index.js}}
at com.tikal.hudson.plugins.notification.model.BuildState.updateArtifact(BuildState.java:205)
at com.tikal.hudson.plugins.notification.model.BuildState.updateArchivedArtifacts(BuildState.java:151)
at com.tikal.hudson.plugins.notification.model.BuildState.updateArtifacts(BuildState.java:137)
at com.tikal.hudson.plugins.notification.Phase.buildJobState(Phase.java:94)
at com.tikal.hudson.plugins.notification.Phase.handle(Phase.java:41)
at com.tikal.hudson.plugins.notification.JobListener.onCompleted(JobListener.java:36)
at hudson.model.listeners.RunListener.fireCompleted(RunListener.java:199)
at hudson.model.Run.execute(Run.java:1810)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
at hudson.model.ResourceController.execute(ResourceController.java:89)
at hudson.model.Executor.run(Executor.java:240)
Failed to notify endpoint 'HTTP:http://localhost:9090/hubot/jenkins' - java.lang.RuntimeException: Adding artifacts mapping 'index.js/archive/http://jnx.lifeplansdev.com/job/XXX/9/artifact/lib/api/api/v1/index.js' - artifacts Map already contains mapping of location 'archive': {Gruntfile.js=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/Gruntfile.js}

, development.json=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/config/development.json}

, config.json=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/config/config.json}

, production.json=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/config/production.json}

, knexfile.js=

{archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/knexfile.js}

, index.js={archive=http://jnx.lifeplansdev.com/job/XXX/9/artifact/index.js}}
Finished: SUCCESS