I am trying to execute auth flow with openvpn auth-pass-verify options.
sample config from openvpn.conf:

auth-user-pass-verify /etc/openvpn/auth2.sh via-file
verify-client-cert require
script-security 3

And the scripts I am trying to use

#!/usr/bin/bash

PATH=$PATH:/usr/local/bin
set -e

env

auth_usr=$(head -1 $1)
auth_passwd=$(tail -1 $1)

if [ $common_name = $auth_usr ]; then
  result=curl -v -X GET -H "Content-type: application/json" -d '{"username"="${auth_usr}"&"password"="${auth_passwd}"}' http://openvpn-ui:8080/auth
  echo $result
  if [ $result = "Authorized" ]; then
    echo "Authorization succeeded"
    exit 0
  else
    echo "Authorization failed"
    exit 1
  fi
else
  echo "Authorization failed"
  exit 1
fi

py:

#!/usr/bin/python3

import sys
import sqlite3
DB_FILE = '/etc/openvpn/db/openvpn-ui.db'


def main():
    with open(sys.argv[1], 'r') as tmpfile:
        username = tmpfile.readline().rstrip('n')
        password = tmpfile.readline().rstrip('n')

    creds = get_password(username)
    if not creds:
        print(f'>> user {username} not defined.')
        sys.exit(1)

    if password != creds[0][1]:
        print(f'>> Incorrect password provided by user {username}.')
        sys.exit(1)

    sys.exit(0)


def get_password(username):
    db = sqlite3.connect(DB_FILE)
    cursor = db.cursor()
    cursor.execute('''select username, password from user where username=?''', (username, ))
    creds = cursor.fetchall()
    db.close()
    return creds


if __name__ == '__main__':
    main()

In each one I have the same error:
WARNING: Failed running command (--auth-user-pass-verify): could not execute external program

Permissions on script -rwxr-xr-x 1 root root 493 May 16 20:52 auth2.sh

I have tried changing permissions already. openvpn running from user nobody.
Any suggestions are welcome.