code: public void billingAccount_voicemail_serviceName_settings_changePassword_POST(String billingAccount, String serviceName, String password) throws IOException {
  		String qPath = "/telephony/{billingAccount}/voicemail/{serviceName}/settings/changePassword";
  		StringBuilder sb = path(qPath, billingAccount, serviceName);
  		HashMap<String, Object>o = new HashMap<String, Object>();
  		addBody(o, "password", password);
  		exec(qPath, "POST", sb.toString(), o);
  	}
docs: Change the voicemail password. It must be 4 digit
  
  REST: POST /telephony/{billingAccount}/voicemail/{serviceName}/settings/changePassword
  @param password [required] The password
  @param billingAccount [required] The name of your billingAccount
  @param serviceName [required]