How to mirror an Azure DevOps repository to a gitlab one

Question

I have deployed my own GitLab server on an Azure VM and I want to mirror an existing Azure DevOps repository into a GitLab one.

When I trigger the mirroring task, I am getting an error.

Host key verification failed.

fatal: Could not read from remote

These are the steps I followed for mirroring :

• settings > repository#js > push > remote > settings on GitLab.
• Expanding the mirroring panel.
• Enter git repo ssh URL.
• ssh://git@ssh.dev.azure.com/v3/xxx/xxx/xxx.
• Replaced the original : by / in front of the v3.
• Add the public key generated by GitLab into my Azure DevOps public key.

Can someone help me to solve this error?