Outgoing webhook sends several requests in a row

Hello,

We are encountering an issue with multiple POST requests being sent to our API.

We created an outgoing webhook in our team, and when we mention this webhook (e.g., @Teams Test 1 test message), it triggers 3 or more identical messages to our API.

Please see the example below:

We tested it using the Node.js example from this repository: Microsoft Teams Samples - Outgoing Webhook (Node.js). This example is suggested by the following article: Add an outgoing webhook.

Additionally, we tested it using a simple Ruby Grape API and encountered the same issue. The Teams outgoing webhook is being sent to our API multiple times.

class API::V1::IncomingWebhooks::Messages < Grape::API
  format :json

  helpers do
    def request_hmac_signature
      request.headers['authorization'].to_s.split[1]
    end

    def valid_hmac?
      serialized_payload_bytes = request.body.read.encode('utf-8')

      key_bytes = Base64.decode64(ENV['TEAMS_SECRET'])
      hmac_sha256 = OpenSSL::HMAC.digest('sha256', key_bytes, serialized_payload_bytes)
      calculated_hmac_value = Base64.encode64(hmac_sha256).strip
      request_hmac_signature == calculated_hmac_value
    end
  end

  namespace 'incoming_webhooks/:id' do
    resources :messages do
      desc 'Creates message'
      post do
        return unauthorized! unless valid_hmac?

        { type: 'message', text: 'Successfully received' }
      end
    end
  end
end

The result is the same

Is there any solution to fix it?

Thanks!