I have forwarded my hosting provider regarding this information, added extra rules in Cloudflare to cache everything and they said that:
In this case, the colleague has already given you the correct information, whereby an error had crept in with the number of Cloudflare accesses. There are at least 167 simultaneous accesses from Cloudflare. In the cases where you run into the vHost limit, the 503 error will even get more than 200, which means that your vHost limit is fully utilized. This behavior is also not normal for Cloudfalre. If Cloudflare has activated caching, i.e. fetches the page once from the server and then delivers it directly from the cache without reloading data from the server for each call, experience has shown that no more than 4-10 simultaneous connections from Cloudflare to the server take place and that is exactly yes also the sense of the CDN. This mass of access clearly indicates a misconfiguration at Cloudflare. Here you would have to check again why Cloudflare generates these masses of simultaneous accesses that should not actually take place and make adjustments to the configuration at Cloudflare. There are no alternatives that can be made by us here, as we have no influence on the accesses from Cloudflare, we could at most block the accesses of the Cloudflare networks.