What is happening
Your EA is attached to a chart but no trades appear. In most cases the code is fine and something is switched off, missing, or misconfigured. Work through the checks below in order.
Common causes
AutoTrading is off (the button in the toolbar is not green). The EA's own 'Allow live trading' box was not ticked when you attached it. There is no smiley face on the chart, meaning the EA is not actually running. The EA's rules simply have not met their entry conditions yet. The symbol or timeframe is wrong for the EA. Trading is disabled for the account or symbol. Or the connection dropped.
Step-by-step fix
Confirm the AutoTrading button in the toolbar is green. Check the top-right of the chart shows a smiley face, not a sad face or an 'x'. Re-attach the EA and, in its settings, enable 'Allow live trading'. In Options, make sure algorithmic trading is allowed and any needed URLs are whitelisted.
Read the Experts and Journal tabs for messages — they usually say exactly why the EA is idle. Verify you are on the chart, symbol, and timeframe the EA expects, and that the market is open.
How to prevent it
Turn on AutoTrading and enable live trading whenever you attach an EA. Test on demo first, watch the Experts log, and confirm the smiley face. Keep the platform connected — a VPS helps if the EA must run continuously.
Broker's fault or yours?
Nearly always a local setting on your side, quickly fixed. The exception is 'AutoTrading disabled by server', where the broker's server has switched off algorithmic trading — a separate issue covered on its own.