# TS1030: '…' modifier already seen.

> The same modifier is written twice on one declaration. Delete the repeated one.

## What it means

A modifier such as `readonly`, `static` or `abstract` can appear only once on a declaration.
It's reported on the second occurrence. Repeated accessibility modifiers are reported as
[TS1028](https://ts-r.dev/errors/TS1028/) instead.

## Example

```ts
export class User {
  readonly readonly id = 1;
}
```

## How to fix

- Remove the duplicate modifier.

Source: https://ts-r.dev/errors/TS1030/