I believed it was due to the bearish market .
Obviously, it went down due to the massive sell-offs in 2018 and up to this year.
What could be the challenge here?
Crypto might be picking interest as of late, but it is does't mean that we are going to see another increase similar to 2017. Perhaps (big) investors confidence are not there yet and they wanted to see a good price increase, maybe in the $6000-$6500 price range before we can see them going back to the ecosystem again to push the price to the next level.
And as others have said, market cap is not a good indicator as well, because shitcoins are just being pump-and-dump. Someone can created a coin and put billions of supply, so it's misleading.