> For the complete documentation index, see [llms.txt](https://docs.fieldmotion.com/fieldmotion-api-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fieldmotion.com/fieldmotion-api-docs/customer/_checkaccountnumberisunique.md).

# \_checkAccountNumberIsUnique

Checks if a Customer's Account Number is Unique

### Parameters

#### id

The id of the customer to be checked.

#### account\_number

The account number of the customer being checked.

### Example

```
FM_api('Customer_checkAccountNumberIsUnique',[
  'id'=>'76943',
  'account_number'=>'12345'
  ]
);
```

### Result

#### On Success

```
{"ok":1}
```

#### On Failure

If the "id" parameter is not included:

```
{"error":"missing or invalid parameter: id"}
```

If the "account\_number" parameter is not included:

```
{"error":"missing or invalid parameter: account_number"}
```

If there is already another Customer with the same account number as the "account\_number" parameter:

```
{"error":"Account number must be unique"}
```


---

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