Market Data 422 Error

Alpaca Market Data
1

I get a 422 - Unprocessable Entity error regardless of the ticker. Here’s an example request:

https://data.alpaca.markets/v2/stocks/IBM/trades?start=2021-06-28T16:33:13Z&end=2021-07-28T16:33:13Z&limit=10000

I’m authenticating with my Paper credentials which I assume is irrelevant. Any assistance would be appreciated.