Sorry, I couldn't find pricing data for that day. The closing price for Bitcoin (BTC) in terms of ZAR on August 21, 2020 was 198,842.01. It was down 3.1% for the day.
DATE
OPEN
HIGH
LOW
CLOSE
August 21 2020
205,147.26
—
—
198,842.01
Daily pricing data for Bitcoin dates back to 7/14/2010, and may be incomplete.