Ninebot ES2 Issue

[rubenhubler]

Hello,
I recently bought a refurbished es2 from the website for super cheap, I noticed that now when i press down on the acceleration throttle, it feels super stiff. Now, when i push it down to go, the throttle just stays down when i release it. I can still move it, but i have to force it to go back up. Anyone know if there is an easy fix or if I need to buy a part (if so, what part?). 2 player games
Thanks in advance!