Can you try below steps, try with fresh pull?
  1. Login with your github account on https://review.trustedfirmware.org/admin/repos/TF-A%2Ftrusted-firmware-a
  2. git clone "ssh://<user>@review.trustedfirmware.org:29418/TF-A/trusted-firmware-a
  3. git push <remote-name> HEAD:refs/for/integration
  4. While pushing if it complains about git hooks, run   scp -p -P 29418 <user>@review.trustedfirmware.org:hooks/commit-msg "trusted-firmware-a/.git/hooks/" and amend your commit (it will give you this hint)

From: TF-A <tf-a-bounces@lists.trustedfirmware.org> on behalf of Nicolas Boulenguez via TF-A <tf-a@lists.trustedfirmware.org>
Sent: 03 April 2021 13:02
To: raghu.ncstate@icloud.com <raghu.ncstate@icloud.com>
Cc: tf-a@lists.trustedfirmware.org <tf-a@lists.trustedfirmware.org>; 'Benjamin Copeland' <ben.copeland@linaro.org>
Subject: Re: [TF-A] please fix incomplete distclean Makefile target
> Are you pushing ssh://<username>@review.trustedfirmware.org:29418/TF-A/trusted-firmware-a HEAD:refs/for/integration?
> Note that 29418 port. That tripped me up initially. It is not clear from your earlier emails where you cloned from(review.trustedfirmware.org or git.trustedfirmware.org).

[] links to [] which recommends
# git clone "https://review.trustedfirmware.org/TF-A/trusted-firmware-a"
I had an existing repository (most contributors probably do) and used
'git add remote' and 'git fetch' instead.

[] recommends
# git push <remote-name> HEAD:refs/for/integration%<topic-branch>
As expected, the host requires a password.

# git push ssh://<user>@review.trustedfirmware.org:29418/TF-A/trusted-firmware-a HEAD:refs/for/integration?
-> fatal: invalid refspec 'HEAD:refs/for/integration?'
Anyhow, the host would require an SSH key.

[] https://developer.trustedfirmware.org/w/tf_a/gerrit-getting-started/
[] https://review.trustedfirmware.org/admin/repos/TF-A%2Ftrusted-firmware-a
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