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

but then I got an error with Permission denied (public key).

I also tried

ssh -Tvvv

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!

Thank you for your patience in reading my post.