# Update a group

With the update group operation, you can add and remove members in an existing group as well as rename the group.

This method encompasses a few ways to update a group:

1. By using add and remove arrays containing phone numbers, you control the group movements. Any list of valid numbers in E.164 format can be added.
2. By using the auto_update object, your customer can add or remove themselves from groups. 
3. You can also add or remove other groups into this group with add_from_group and remove_from_group.

#### Other group update info

- The request will not be rejected for duplicate adds or unknown removes.
- The additions will be done before the deletions. If an phone number is on both lists, it will not be apart of the resulting group.
- Updating a group targeted by a batch message scheduled in the future is allowed. Changes will be reflected when the batch is sent.

Endpoint: POST /xms/v1/{service_plan_id}/groups/{group_id}
Version: v1
Security: BearerAuth

## Path parameters:

  - `service_plan_id` (string, required)
    Your service plan ID. You can find this on your Dashboard.
    Example: "jd63jf88477ll123ab4567cd89012ef3"

  - `group_id` (string, required)
    ID of a group that you are interested in getting.

## Request fields (application/json):

  - `add` (array)
    Add a list of phone numbers (MSISDNs) to this group. The phone numbers are a strings within an array and must be in [E.164 format](https://community.sinch.com/t5/Glossary/E-164/ta-p/7537).

  - `remove` (array)
    Remove a list of phone numbers (MSISDNs) to this group.The phone numbers are a strings within an array and must be in [E.164 format](https://community.sinch.com/t5/Glossary/E-164/ta-p/7537).

  - `name` (string)
    The name of the group. Omitting name from the JSON body will leave the name unchanged. To remove an existing name set, name explicitly to the JSON value null.

  - `add_from_group` (string)
    Copy the members from the another group into this group.

Constraints:
Must be valid group ID

  - `remove_from_group` (string)
    Remove the members in a specified group from this group.

Constraints:
Must be valid group ID

  - `auto_update` (object)

  - `auto_update.to` (string, required)
    Short code or long number addressed in [MO](https://community.sinch.com/t5/Glossary/MO-Mobile-Originated/ta-p/7618).

Constraints:

Must be valid phone number or short code which has been provisioned by your account manager.
    Example: "+15551231234"

  - `auto_update.add` (object)
    Keyword to be sent in MO to add MSISDN to a group

  - `auto_update.add.first_word` (string, required)
    Opt-in keyword like "JOIN" if _auto_update.to_ is dedicated long/short number or unique brand keyword like "Sinch" if it is a shared short code.
    Example: "Sinch"

  - `auto_update.add.second_word` (string)
    Opt-in keyword like "JOIN" if _auto_update.to_ is shared short code.
    Example: "JOIN"

  - `auto_update.remove` (object)
    Keyword to be sent in MO to remove MSISDN to a group

  - `auto_update.remove.first_word` (string, required)
    Opt-out keyword like "LEAVE" if _auto_update.to_ is dedicated long/short number or unique brand keyword like "Sinch" if it is a shared short code.
    Example: "LEAVE"

  - `auto_update.remove.second_word` (string)
    Opt-out keyword like "LEAVE" if _auto_update.to_ is shared short code.

## Response 200 fields (application/json):

  - `id` (string)
    The ID used to reference this group.
    Example: "01FC66621VHDBN119Z8PMV1QPQ"

  - `name` (string)
    Name of group if set.
    Example: "My new customers"

  - `size` (integer)
    The number of members currently in the group.
    Example: 2

  - `created_at` (string)
    Timestamp for group creation. Format: YYYY-MM-DDThh:mm:ss.SSSZ

  - `modified_at` (string)
    Timestamp for when the group was last updated. Format: YYYY-MM-DDThh:mm:ss.SSSZ

  - `child_groups` (array)
    Phone numbers [MSIDNs](https://community.sinch.com/t5/Glossary/MSISDN/ta-p/7628) of child group will be included in this group. If present then this group will be auto populated.

Constraints: Elements must be group IDs.
    Example: ["01FC66621VHDBN119Z8PMV1AHY"]

  - `auto_update` (object)

  - `auto_update.to` (string, required)
    Short code or long number addressed in [MO](https://community.sinch.com/t5/Glossary/MO-Mobile-Originated/ta-p/7618).

Constraints:

Must be valid phone number or short code which has been provisioned by your account manager.
    Example: "+15551231234"

  - `auto_update.add` (object)
    Keyword to be sent in MO to add MSISDN to a group

  - `auto_update.add.first_word` (string, required)
    Opt-in keyword like "JOIN" if _auto_update.to_ is dedicated long/short number or unique brand keyword like "Sinch" if it is a shared short code.
    Example: "Sinch"

  - `auto_update.add.second_word` (string)
    Opt-in keyword like "JOIN" if _auto_update.to_ is shared short code.
    Example: "JOIN"

  - `auto_update.remove` (object)
    Keyword to be sent in MO to remove MSISDN to a group

  - `auto_update.remove.first_word` (string, required)
    Opt-out keyword like "LEAVE" if _auto_update.to_ is dedicated long/short number or unique brand keyword like "Sinch" if it is a shared short code.
    Example: "LEAVE"

  - `auto_update.remove.second_word` (string)
    Opt-out keyword like "LEAVE" if _auto_update.to_ is shared short code.

## Response 400 fields (application/json):

  - `code` (string)
    The error code. See [error codes](https://developers.sinch.com/docs/sms/api-reference/status-codes/).

  - `text` (string)
    The human readable description of the error.

## Response 403 fields (application/json):

  - `code` (string)
    The error code. See [error codes](https://developers.sinch.com/docs/sms/api-reference/status-codes/).

  - `text` (string)
    The human readable description of the error.