exp bug

I am quite new to this website and the trading system but almost immediately I have exp 0% efficency and I can do nothing about it why?

Xp % eff passively drains constantly. If you run out of dp, your xp eff starts to drain, and you gain less xp until you reach 0%, which then you will not gain anxp eff. You can recover xp efficiency by gaining dp and filling up the efficiency bar.
To prevent players inactive in the trading system from soaking up dp, the dp drain rate is much higher when one’s xp efficiency is 0%. Get at least 1% xp efficiency so you are not hindered by the massive dp drain rate.

An FAQ here: https://gist.github.com/KceGio/b4f15bb85ed1c493fb96da5cfa3e8541

Finally thats why I lost my 70 dp