Trouble on setting SSH key in GItlab

I’ve followed the Gitlab instructions to set up an SSH key.

After everything is completed, I test my settings with

ssh -T git@gitlab.com

but then I got an error with

git@gitlab.com: Permission denied (public key).

I also tried

ssh -Tvvv git@gitlab.com

to find out the problems, as below. But I can’t figure out how to fix it, does anybody have an idea, or could share suggestions? Thank you very much!




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