I have a php application that has the following code:

$response = Http::withHeaders([
                            'Content-Type' => 'application/json',
                        ])->post($webhook->url, [
                            'type' => 'message',
                            'attachments' => [
                                [
                                    'contentType' => 'application/vnd.microsoft.card.adaptive',
                                    'content' => [
                                        'type' => 'AdaptiveCard',
                                        'body' => [
                                            [
                                                'type' => 'TextBlock',
                                                'size' => 'Medium',
                                                'weight' => 'Bolder',
                                                'text' => 'New Ticket: ' . $requesterName,
                                                'color' => 'Accent',
                                                'wrap' => true,
                                                'spacing' => 'Small'
                                            ],
                                            [
                                                'type' => 'ColumnSet',
                                                'columns' => [
                                                    [
                                                        'type' => 'Column',
                                                        'width' => 'stretch',
                                                        'items' => [
                                                            [
                                                                'type' => 'TextBlock',
                                                                'size' => 'Default',
                                                                'weight' => 'Bolder',
                                                                'text' => $ticket['subject'],
                                                                'spacing' => 'Small',
                                                                'wrap' => true
                                                            ]
                                                        ]
                                                    ],
                                                    [
                                                        'type' => 'Column',
                                                        'width' => 'auto',
                                                        'items' => [
                                                            [
                                                                'type' => 'TextBlock',
                                                                'text' => '(P' . (5 - $ticket['priority']) . ')',
                                                                'color' => $ticket['priority'] == 4 ? 'Attention' : 'Good',
                                                                'spacing' => 'None'
                                                            ]
                                                        ]
                                                    ]
                                                ],
                                                'spacing' => 'Small'
                                            ],
                                            [
                                                'type' => 'TextBlock',
                                                'text' => $ticket['description_text'],
                                                'wrap' => true,
                                                'spacing' => 'Small',
                                                'color' => 'Default',
                                                'id' => 'description',
                                                'isVisible' => false
                                            ],
                                            [
                                                'type' => 'ActionSet',
                                                'actions' => [
                                                    [
                                                        'type' => 'Action.OpenUrl',
                                                        'title' => 'View Ticket',
                                                        'url' => $endpoint . $ticket['id'],
                                                        'style' => 'positive'
                                                    ],
                                                    [
                                                        'type' => 'Action.ToggleVisibility',
                                                        'title' => 'Show Description',
                                                        'targetElements' => ['description']
                                                    ]
                                                ],
                                                'spacing' => 'Small'
                                            ]
                                        ],
                                        '$schema' => 'http://adaptivecards.io/schemas/adaptive-card.json',
                                        'version' => '1.2'
                                    ]
                                ]
                            ]
                        ]);

This all works fine but i also want to tag either the team or the channel so users get a notification when it posts.

I tired this to test but it just comes with <at>channel</at> in the message on teams, and is not tagged.

           $response = Http::withHeaders([
                                'Content-Type' => 'application/json',
                            ])->post($webhook->url, [
                                'type' => 'message',
                                'text' => '<at>channel</at>', // Mention the channel here
                                'attachments' => [
                                    [
                                        'contentType' => 'application/vnd.microsoft.card.adaptive',
                                        'content' => [
                                            'type' => 'AdaptiveCard',
                                            '$schema' => 'http://adaptivecards.io/schemas/adaptive-card.json',
                                            'version' => '1.0',
                                            'body' => [
                                                [
                                                    'type' => 'TextBlock',
                                                    'text' => 'This is a message with an Adaptive Card and a mention.',
                                                ],
                                            ],
                                        ],
                                    ],
                                ],
                                'msteams' => [
                                    'entities' => [
                                        [
                                            'type' => 'mention',
                                            'text' => '<at>channel</at>',
                                            'mentioned' => [
                                                'id' => $webhook->channel_id,
                                                'name' => 'channel',
                                            ],
                                        ],
                                    ],
                                ],
                            ]);

Can any one offer any guidance?