How to disable cached responses from node fetch? (Microsoft Bookings API)

Question

I have built a simple fetch wrapper which can send post requests. When I try to send a post request to this endpoint (https://cdn.utm-shop.de/bookings/availability?serviceId=xxxxxxxxxxx&dateFrom=2024-03-20&dateTo=2024-04-20 ) then I receive an correct response. Then I change some data and call this endpoint again. And it still respond with the old data. Maybe after 2-5 Minutes it responds correctly. When I call the endpoint with curl or Postman, it responses correctly immediately.

async function post(url, body = {}, headers = {}) {
const requestOptions = {
    method: 'POST',
    headers: headers,
    body: body
};

return await fetch(url, requestOptions).then(response => {
    return response.json()
}).then(data => {
    return data
})
}

I have tried following solutions which not worked for me:

Added no-cache header

Added cache:no-cache to requestOption

Added a dummy query parameter with the timestamp, so the requests are different