404 error

Getting current ticker data...
Success.
Getting list of assets...
Success.
Tracking 201 symbols.
Getting historical data...
Traceback (most recent call last):
File "C:/Users/colef/PycharmProjects/Code/Python/Momentum-Trading-Example-master/algo.py", line 400, in
run(get_tickers(), market_open, market_close)
File "C:/Users/colef/PycharmProjects/Code/Python/Momentum-Trading-Example-master/algo.py", line 90, in run
minute_history = get_1000m_history_data(symbols)
File "C:/Users/colef/PycharmProjects/Code/Python/Momentum-Trading-Example-master/algo.py", line 40, in get_1000m_history_data
size="minute", symbol=symbol, limit=1000
File "C:\Users\colef\Anaconda3\lib\site-packages\alpaca_trade_api\polygon\rest.py", line 123, in historic_agg
raw = self.get(path, params)
File "C:\Users\colef\Anaconda3\lib\site-packages\alpaca_trade_api\polygon\rest.py", line 37, in get
return self._request('GET', path, params=params, version=version)
File "C:\Users\colef\Anaconda3\lib\site-packages\alpaca_trade_api\polygon\rest.py", line 33, in _request
resp.raise_for_status()
File "C:\Users\colef\Anaconda3\lib\site-packages\requests\models.py", line 940, in raise_for_status
raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 404 Client Error: Not Found for url: https://api.polygon.io/v1/historic/agg/minute/ARLO?limit=1000&apiKey=xxxxxxxxxxxxxxxxxxxxxxxxxxxx

Process finished with exit code 1

Can someone please help me with this. I have a valid Brokerage account but it still gives me this error.