your connection is rejected while another connection is open under the same account

Hey, I am running into an error with multiple data feeds, e.g. with the example https://github.com/alpacahq/alpaca-backtrader-api/blob/master/sample/strategy_multiple_datas.py

Error:
`alpaca_trade_api\stream2.py", line 52, in _connect raise Exception(f"Error while connecting to {self._endpoint}:" Exception: Error while connecting to wss://data.alpaca.markets/stream:your connection is rejected while another connection is open under the same account `

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It's working with one data feed, and I restarted my computer, tried another account, ... & the same message appears.

Running Windows 10, Python 3.6

*My guess* is, that it is related to me not having a "full" account because I'm non-US and the datafeed might only allow one feed per paper account?