How do I set or change the leader account in Replikanto so that trades are copied from the correct account?

Replikanto copies trades from the one account you designate as the leader to the follower accounts you enable. When trades are not being copied, the leader selection inside the Replikanto window is the first thing to check.

Set the leader account

Open the Replikanto window in NinjaTrader. If it did not load with your workspace, open it from New > FlowBots > Replikanto.
Select the account you want to designate as the leader in the Replikanto window.
Confirm this is the same account you are actually placing orders from in NinjaTrader. Replikanto only copies trades placed on the account currently set as leader, so trading from a different account produces no copies.
Select the correct instrument in the Replikanto tab. Trades are not copied when the instrument is not selected properly.
Enable the follower accounts that should receive the copies. Followers have to be selected individually the first time. The Toggle On button only restores accounts you previously turned off with Toggle Off, so it will not enable followers from scratch.

Changing the leader account, instrument or Method during a trade

Starting with Replikanto 1.7.0.0, the leader account, the instrument and the copy Method cannot be changed while a trade is open on the tab, that is, while the leader account holds a position or any follower on the tab has an open position or a working order. The selectors are greyed out, and hovering them shows: "At least one follower account on this tab has an open position or a working order. Flatten it, or wait for the trade to finish, before changing this setting." A change coming from a linked chart is refused and switched back. Wait for the trade to close or flatten the followers, then make the change. If the selectors stay locked when nothing is open, you can turn off Lock follower settings while in a trade in the General properties of the tab. See Why can't I change follower settings during a trade?

If the account you want is not in the list

Replikanto reads the account list from NinjaTrader's connection when it starts, so accounts added while Replikanto is already running will not appear. There is no in-window refresh for this. To pick up new accounts:

Close all Replikanto windows.
Restart NinjaTrader.
Reopen Replikanto from New > FlowBots > Replikanto.

If an account is still missing, open the Accounts tab in NinjaTrader's Control Center and confirm it is listed with an active connection. Replikanto only lists accounts from a live connection.

Check as well whether NinjaTrader's Global Simulation Mode is enabled. With that mode on, Replikanto follower accounts are not visible.

Change the leader without restarting

You do not need to restart anything to work with a different leader. Replikanto lets you keep one tab open per leader account.

Open one Replikanto tab for each leader account you use. Press the + tab to add one, or right-click an existing tab to duplicate it together with its settings.
All open tabs are active at the same time. When you trade a given instrument on the leader side, the matching tab handles the copy to its followers automatically.
To make a different leader active, switch to that account's tab instead of the one you were using before.
After adding or duplicating a tab, change the instrument in the new tab so the same order is not replicated twice. (The instrument can only be changed while no trade is open on that tab.)
There is no need to restart NinjaTrader, restart the VPS, or disconnect and reconnect TradingView when moving between leader tabs.

A single tab cannot copy more than one instrument at a time, so open one tab per instrument you trade. Separate Replikanto windows work the same way as tabs if you prefer them.

Which account to use as the leader

Any account type can act as the leader, whether it is a Sim, Live, or Funded account.
Where possible, use a leader of the same type as the followers. For example, with three funded accounts, use one of them as the leader rather than a Sim account. Keeping every account on one type reduces the moments when they can drift out of sync.

When you trade through TradingView

Orders placed in TradingView reach Replikanto through NinjaTrader rather than directly. Set the Tradovate account that is connected to NinjaTrader as the leader in Replikanto, and place your TradingView orders on that same account. When trading the leader from external software, it is recommended to monitor the follower accounts in NinjaTrader Desktop.

If trades still are not copied

Follower chart windows do not need to be open. Replikanto copies in the background as long as the Replikanto tabs themselves are running.
A follower account that is disarmed or disconnected will not receive copies.
A disruption between NinjaTrader and the broker pauses copying until the connection is restored.

For the full list of situations that stop copying, see When Replikanto will not copy the trades?. If the problem continues after these checks, reach out to support for further technical help.