Is my internet not good enough?

Recently I'm losing bullet games cause my premoves can take upwards of 0.4 seconds. In blitz my game randomly disconnects taxing 15-30 seconds. This is really frustrating as I basically lose a game if it goes to a time scramble. 

My download speed is about 12 Mbps and upload is about 4 Mbps. Is that not enough to play lag free or with minimal lag?

We can't tell. We don't have access to any stats summarizing your connectivity.

The stats you quote aren't really relevant unless you are trying to figure out if streaming movies will work. They don't tell you how long it takes for your ISP to actually achieve such a speed.

Usually, people look at their ping measurements to see how long it takes for Chess.com servers to respond. You can compare it to other servers to see if Chess.com is faster or slower.

But it still looks like you are winning more of your games by timeout than you are losing...

Winning Losing

7 Days 60% 39%

All time 79% 31%

This is from your last game and shows several white moves at 0.1 seconds. (You were white.)

I hav between 0.1s - 0.7s on my HUAWEI. Susge