Update an existing lead
Supports non-destructive patches. Nested `contacts` cannot be updated through this endpoint -- use the Contacts API instead.
**status**: See `status` and `status_id` guidance on the create endpoint.
**custom.FIELD_ID** (optional): See `custom.FIELD_ID` guidance on the create endpoint. You can also unset a single field, e.g.:
```json
{ "custom.cf_v6S011I6MqcbVvB2FA5Nk8dr5MkL8sWuCiG8cUleO9c": null }
```
If the custom field accepts multiple values, you can specify `.add` or `.remove` as part of the field key to add/remove a single value to/from a list of values, e.g.:
```json
{ "custom.cf_v6S011I6MqcbVvB2FA5Nk8dr5MkL8sWuCiG8cUleO9c.add": "Wednesday" }
```
adds "Wednesday" to the list of values which already exist on the given lead.