Git@gitlab.com: Permission denied (publickey)

it first time to deploy repo at gitlab, so i’m created repo and going to terminal at my project and let :
1- git init
2- git add .
3- git commit -m “first commit”
4- git remote add origin “repo_name”
5- git push -u origin master
but i’m face problem :
git@gitlab.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
note: i’m added ssh key at my account so i don’t know hoe to solve it