Well if you just take a look at the whole chart (
https://coinmarketcap.com/currencies/okcash/) you'll clearly see that this is expected.
The coin got pumped at the beginning of the month and continued to rise for some time. It reached the highest ever on 19 September.
Well if you deal with new coins a lot you'd probably know that they are just there for pumps and dumps. Once the coin gets pumped and keeps increasing that's the time you need to keep an eye open.
Because soon enough the price will go down which would indicate that it's the end of the pump and you should sell immediately.
Good Luck with another coin.