A recent surge in traffic to a popular online service has resulted in an overwhelming number of requests being made to its underlying systems. This has led to the server exceeding its maximum allowed requests per time period, causing all further requests to be refused.
The issue is not unique to this specific service and can occur when high volumes of traffic are directed towards any web-based application or API. To mitigate such issues, many services implement rate limiting measures, which restrict the number of requests that can be made within a given timeframe.
In this instance, the service’s administrators have been notified of the issue and are working to address the root cause and implement additional measures to prevent similar overload in the future.
Source: https://www.cbssports.com/college-basketball/news/bracketology-bubble-watch-north-carolina-indiana-texas-looking-for-wins-to-boost-ncaa-tournament-resumes