My account was banned from logging in.

Hello!Please tell me why my account can not log in,I didn't break the balance of the game.I gave my friend some gold coins the day before yesterday.A few days ago, a friend gave me some gold coins to buy a horse.What's important is that I'm only lv46. I have never bought gold or used any exploits.
Please help me to solve this problem.
Level 46 Human Rogue on the PvP Server -> Name: Cestlavies
Please help me to solve this problem.
Level 46 Human Rogue on the PvP Server -> Name: Cestlavies