Yes. Trading Gold / XAUUSD is not banned, and trading one instrument is not banned.
The dashboard monitors whether your account becomes excessively concentrated in one symbol and one direction. For example, if after at least 10 closed trades, 70% or more of your trades or exposure are all XAUUSD buys or all XAUUSD sells, the one-sided concentration metric may become active.
During Challenge / Pro Challenge, this is a soft warning only.
On Funded / Instant accounts, it matters mainly if the condition remains active when payout is requested.
Related Terms: Sections 7.12.4, 7.20.3
