# T405

> event not available for this subscription

**Severity** Error

The handler uses an event that the subscription's source does not deliver. Bar-based sources (`ohlcv`, `oi`, `funding`, `liquidations`, `vd`, `cvd`, `flow`) have `open`, `update` and `close`; only `data.trades` has `trade(tr)`, and that is its only event.

Use an event the source supports, or subscribe to the source that delivers the event you want.

## Failing example

```flowscope
script "Big print marker"
data chart = subscribe(data.ohlcv)
plot big = plot.point(title: "Big print", color: color.poc)
on chart.trade(tr) {
  if tr.notional > 1_000_000.0 {
    big.plot(tr.price)
  }
}
```

## Fixed example

```flowscope
script "Big print marker"
data tape = subscribe(data.trades, minNotional: 1_000_000.0)
plot big = plot.point(title: "Big print", color: color.poc)
on tape.trade(tr) {
  big.plot(tr.price)
}
```

## Related

- [T406](/docs/scripting/reference/diagnostics/t406)
- [T407](/docs/scripting/reference/diagnostics/t407)