Turns the placement's Limits switch off: its limits and counters are deleted and delivery is no longer capped. A placement without limits answers success. Requires UPDATE share on the placement's site and MANAGE_CAPPING_AND_LIMITATIONS.
using var client = new HttpClient();
var request = new HttpRequestMessage(new HttpMethod("DELETE"), "https://YOUR-NETWORK-DOMAIN/rest-api/placement/3001/limits.do");
request.Headers.Add("X-Api-Key", "YOUR_API_KEY");
var response = await client.SendAsync(request);
Console.WriteLine(await response.Content.ReadAsStringAsync());