Getting filled outside of intraday range

[RobinHood]

I've doing a complete post-analysis of my trades and noticed that in one particular trade I was filled on a "sell @ market" 3.7% below the actual low of that day . This was a volatile, low-volume, Chinese stock trading on NASDAQ.

I can understand slippage, but below an actual daily range?
I thought this only happens on otcbb?