To be honest, CMC has been accused of manipulating prices and display fake volume several times so i wouldn't be surprised if they messed with something yesterday.
Totally not manipulation at all but misleading in my own view as I noticed back then a certain coin hits an impressive high gain performance but when you look at the exchange itself where that coin was primarily traded, there were only identical orders of it that's why CMC recorded the average price.
If a trader really cares for their coins, they will not use CMC as price basis.
On coinmarketcap, historical value of bitcoin on 6th of Oct 2019 is 7,988.16 for Close.
Closing price for same date (checked on tradingview on multiple exchanges, and Bitstamp directly) was 7860 usd.
That's almost 2% increase for coinmarketcap. Wonder if they purposely screwing people...
Exchanges have different rates. Coinmarketcap takes the average IIRC.
Don't rely on CMC about coins price. Head to exchange instead where that specific coin is listed.