Downloading from BOX drive is slow. 7MB / S → 128KB / S Capacity limit?

Downloading from BOX drive is slow. Two weeks ago, I started downloading the data stored in the BOX drive to my local HDD. At first, it was able to download at a speed of about 7MB / S, but it became slower day by day, and as of today it has reached 128KB / S. Does the BOX drive have a download capacity limit? It's been said that it's slow when many people are connected to the internet, but is that so slow to download? If there is a capacity limit, will it be reset at the end of the month? Anyway, it's useless at the current speed. I have 3TB of data that I want to download locally. What is the cause of the slowdown? Is it like a mobile phone capacity limit when you are using it? Is there a way to make the download more efficient?