got (error in Gerrit backend) when submitting patches

[cfig]

Greetings,

Need help, I got following error message when running "repo upload", any ideas about what "error in Gerrit backend" means?

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[PASSED] repohooks for platform/build passed

Upload project build/make/ to remote branch master:

  branch master ( 1 commit, Wed Aug 22 15:50:37 2018 +0800):

         9a68b852 use BOARD_PREBUILT_DTBOIMAGE in target-files-package

to https://android-review.googlesource.com/ (y/N)? y

To https://android-review.googlesource.com/platform/build

 ! [remote rejected]     master -> refs/for/master (error in Gerrit backend)

error: failed to push some refs to 'https://android-review.googlesource.com/platform/build'

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[FAILED] build/make/     master          (Upload failed)

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