# TRADING & TROUBLESHOOTING

- [Why is FaceID re-authentication required during trading?](https://bullbit.gitbook.io/help-center/trading-and-troubleshooting/why-is-faceid-re-authentication-required-during-trading.md): Why does the App request FaceID re-authentication during trading?
- [Why liquidation before price reached?](https://bullbit.gitbook.io/help-center/trading-and-troubleshooting/why-liquidation-before-price-reached.md): Why was my position liquidated even though the chart price didn't reach that level?
- [Why is displayed PnL different from realized PnL?](https://bullbit.gitbook.io/help-center/trading-and-troubleshooting/why-is-displayed-pnl-different-from-realized-pnl.md)
- [How to verify balance and chart display issues?](https://bullbit.gitbook.io/help-center/trading-and-troubleshooting/how-to-verify-balance-and-chart-display-issues.md): I suspect a display error or the chart is lagging. What should I do?