ChannelMessage.UpdatePolicyViolation.All

const options = {
	authProvider,
};

const client = Client.init(options);

const chatMessage = {
  policyViolation: {
    policyTip: {
      generalText: 'This item has been blocked by the administrator.',
      complianceUrl: 'https://contoso.com/dlp-policy-page',
      matchedConditionDescriptions: ['Credit Card Number']
    },
    verdictDetails: 'AllowOverrideWithoutJustification,AllowFalsePositiveOverride',
    dlpAction: 'BlockAccess'
  }
};

await client.api('/teams/e1234567-e123-4276-55555-6232b0e3a89a/channels/a7654321-e321-0000-0000-123b0e3a00a/messages/19:[email protected]')
	.update(chatMessage);

Import-Module Microsoft.Graph.Teams

$params = @{
	policyViolation = @{
		policyTip = @{
			generalText = "This item has been blocked by the administrator."
			complianceUrl = "https://contoso.com/dlp-policy-page"
			matchedConditionDescriptions = @(
			"Credit Card Number"
		)
	}
	verdictDetails = "AllowOverrideWithoutJustification,AllowFalsePositiveOverride"
	dlpAction = "BlockAccess"
}
}

Update-MgTeamChannelMessage -TeamId $teamId -ChannelId $channelId -ChatMessageId $chatMessageId -BodyParameter $params

# Code snippets are only available for the latest version. Current version is 1.x
from msgraph import GraphServiceClient
from msgraph.generated.models.chat_message import ChatMessage
from msgraph.generated.models.chat_message_policy_violation import ChatMessagePolicyViolation
from msgraph.generated.models.chat_message_policy_violation_policy_tip import ChatMessagePolicyViolationPolicyTip
from msgraph.generated.models.chat_message_policy_violation_verdict_details_types import ChatMessagePolicyViolationVerdictDetailsTypes
from msgraph.generated.models.chat_message_policy_violation_dlp_action_types import ChatMessagePolicyViolationDlpActionTypes
# To initialize your graph_client, see https://learn.microsoft.com/en-us/graph/sdks/create-client?from=snippets&tabs=python
request_body = ChatMessage(
	policy_violation = ChatMessagePolicyViolation(
		policy_tip = ChatMessagePolicyViolationPolicyTip(
			general_text = "This item has been blocked by the administrator.",
			compliance_url = "https://contoso.com/dlp-policy-page",
			matched_condition_descriptions = [
				"Credit Card Number",
			],
		),
		verdict_details = ChatMessagePolicyViolationVerdictDetailsTypes.AllowOverrideWithoutJustification | ChatMessagePolicyViolationVerdictDetailsTypes.AllowFalsePositiveOverride,
		dlp_action = ChatMessagePolicyViolationDlpActionTypes.BlockAccess,
	),
)

result = await graph_client.teams.by_team_id('team-id').channels.by_channel_id('channel-id').messages.by_chat_message_id('chatMessage-id').patch(request_body)