Microsoft is going to introduce on March 6 a new free tier for Azure Cosmos DB, globally distributed and multi-model, cloud database. Officials accidentally announced it on March 4, but will officially announce it today. The official Azure Cosmos DB Twitter page reports that it was accidentally announced due to a technical failure. The free level will be authoritatively advertised and accessible on March 6. 
Microsoft introduced Azure Cosmos DB, service "for managing data at planet-scale" originated in May 2017. Azure Cosmos DB was designed from Microsoft's existing NoSQL Document DB database. Its code name was "Project Florence" and Microsoft considers it to be a "born in the cloud/original cloud" database that is designed to be scalable and convenient for customers of all types.
Currently, Microsoft charges an hourly fee for providing access and storage to Azure Cosmos. Prior to the initiation of the free tier, Microsoft previously proposed customers the opportunity to try Cosmos DB for free, using the local Azure Cosmos DB emulator to improve and test ready-to-produce applications. There is also a possibility of a trial period of 30 days. 
Microsoft has made free versions available for a number of its products, as well as Power BI and Teams, as a way to convince customers to switch to paid versions.