Getting 'unknown sender' notification when creating google calender event via service account

[mster429]

const auth = new GoogleAuth({
      scopes: [
        'https://www.googleapis.com/auth/calendar',
        'https://www.googleapis.com/auth/calendar.events'
      ],
      keyFile: './src/serviceaccount.json',
      clientOptions: {
        subject: '[email protected]'
      }
    });

    const calendar = google.calendar({ version: 'v3', auth: auth });

    const apiResponse = await calendar.events.insert({
      calendarId: "[email protected]",
      conferenceDataVersion: 1,
      requestBody: {
        start: {
          dateTime: "2024-10-10T08:00:00+09:00",
        },
        end: {
          dateTime: "2024-10-10T08:30:00+09:00",
        },
        attendees: [{ email: "[email protected]" }, { email: "[email protected]" }],
        summary: 'Test Event',
        description: 'Test Event created',
        guestsCanInviteOthers: true,
        conferenceData: {
          createRequest: {
            requestId: randomUUID(),
            conferenceSolutionKey: {
              type: 'hangoutsMeet'
            }
          }
        },
        reminders: {
          useDefault: false,
          overrides: [],
        },
        guestsCanModify: true,
        visibility: 'default',
      }
    });

I am using the above code to create a calender event using google calender api via google service account. sendUpdates parameter is false so that I don't get any notification via google about the event creation. But when I try this only the first time I am getting the below notification from google and i need to suppress/ disable it and i need help to get this resolved. Thanks in advance