Ansible prompt "No existing session" in manual executing the playbook

Question

Current situation:

I can ssh to SwitchA with ssh client.

With the same playbook, it can ssh to the SwitchA by cronjob, but I can't execute the playbook manually and got the below error message.

How can I solve this issue and make it successful in executing this playbook manually?

ansible-playbook -i SwitchA.yml playbook.yml

Ansible debugging

<172.26.192.229> connection transport is cli
<172.26.192.229> using connection plugin network_cli (was local)
<172.26.192.229> starting connection from persistent connection plugin
<172.26.192.229> local domain socket does not exist, starting it
<172.26.192.229> control socket path is /home/xxxx/.ansible/pc/67b0b2e86d
<172.26.192.229> loaded cliconf plugin for network_os ce
<172.26.192.229> 
The full traceback is:
Traceback (most recent call last):
  File "/usr/local/lib/python3.6/site-packages/ansible/plugins/connection/paramiko_ssh.py", line 352, in _connect_uncached
    **ssh_connect_kwargs
  File "/usr/local/lib/python3.6/site-packages/paramiko/client.py", line 412, in connect
    server_key = t.get_remote_server_key()
  File "/usr/local/lib/python3.6/site-packages/paramiko/transport.py", line 834, in get_remote_server_key
    raise SSHException("No existing session")
paramiko.ssh_exception.SSHException: No existing session

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/bin/ansible-connection", line 104, in start
    self.connection._connect()
  File "/usr/local/lib/python3.6/site-packages/ansible/plugins/connection/network_cli.py", line 327, in _connect
    ssh = self.paramiko_conn._connect()
  File "/usr/local/lib/python3.6/site-packages/ansible/plugins/connection/paramiko_ssh.py", line 245, in _connect
    self.ssh = SSH_CONNECTION_CACHE[cache_key] = self._connect_uncached()
  File "/usr/local/lib/python3.6/site-packages/ansible/plugins/connection/paramiko_ssh.py", line 368, in _connect_uncached
    raise AnsibleConnectionFailure(msg)
ansible.errors.AnsibleConnectionFailure: No existing session

fatal: [SwitchA]: FAILED! => {
    "msg": "No existing session"
}

I found there a difference
Cronjob

        "ansible_playbook_python": "/usr/bin/python2", 
        "ansible_python_interpreter": "python3", 
        "ansible_version": {
            "full": "2.9.27", 
            "major": 2, 
            "minor": 9, 
            "revision": 27, 
            "string": "2.9.27"
        }

Manual Execution

                "ansible_python_interpreter": "python3",
                "ansible_version": {
                    "full": "2.8.1",
                    "major": 2,
                    "minor": 8,
                    "revision": 1,
                    "string": "2.8.1"
                }

My Playbook

  connection: local
  serial: 30
  gather_facts: no
  vars:
    cli:
      host: "{{ ansible_host }}"
      port: 22
      username: "{{ username }}"
      password: "{{ password }}"
      transport: cli

    - name: "Testing"
      ce_command:
        commands: "{{ command_list }}"
        provider: "{{ cli }}"
        timeout: 900
      register: MyResult

SwitchA debug:

SSH/7/RECV_PKT:Received ssh2 msg kex init packet.
SSH/7/KEX_DERECTION:Kex for direction is in.
SSH/7/CHOOSE_ENCRYPT:Chose encryption algorithm:aes128-ctr.
SSH/7/CHOOSE_MAC:Chose MAC algorithm:hmac-sha2-256.
SSH/7/KEX_DERECTION:Kex for direction is out.
SSH/7/CHOOSE_ENCRYPT:Chose encryption algorithm:aes128-ctr.
SSH/7/CHOOSE_MAC:Chose MAC algorithm:hmac-sha2-256.
SSH/7/CHOOSE_KEX:Choose Kex algorithm:diffie-hellman-group16-sha512.
SSH/7/KEX_UNSUPPORT:Unsupported Kex algorithm:ecdsa-sha2-nistp256!
SSH/7/FSM_MOVE:FSM moved from SSH_Sub1_KEX_Init to SSH_Sub1_KEX_GRP_Init.
SSH/7/RECV_PKT:Received ssh2 msg kexdh init packet.
SSH/7/FSM_MOVE:FSM moved from SSH_Sub1_KEX_GRP_Init to SSH_Sub1_KEX_GRP_Reply.
SSH/7/no_info:Begin to compute the dh shared key.
SSH/7/no_info:The line phylink is null. ulLineIndex = 6
SSH/7/no_info:Fail to inform to dh key result. ulRet = 0x1