Ansible: Failed to connect to the host via ssh: Host key verification failed

ansible-playbook -v --private-key $SSH_PRIVATE_KEY playbooks/letsencrypt.yml
Using /builds/devops/letsencrypt/ansible.cfg as config file

PLAY [Обновление сертификатов Let's Encrypt] ***********************************

TASK [Gathering Facts] *********************************************************
fatal: [specialistoff.net]: UNREACHABLE! => {"changed": false, "msg": "Failed to connect to the host via ssh: Host key verification failed.", "unreachable": true}

PLAY RECAP *********************************************************************
specialistoff.net            : ok=0    changed=0    unreachable=1    failed=0    skipped=0    rescued=0    ignored=0