Well, after I investigated the coins I saw they were low volume and listed on a small exchange.
Keep in mind, the smaller the volume the easier the price will be to manipulate.
For example, you can buy at $ 1 and sell it at $ 10 and you who buy it at $ 10 will make the price go up to 1000%.
The illustration is very easy to understand, and it is true. That is, with low trading volume, we can easily manipulate market prices and don't need the help of whales to do that.
And it is possible that this moment is used as a marketing tool for scammers who like to promise high ROI when you invest a certain amount of money, once you buy the coins, it is a sell order made by a scammer.