https://wccftech.com/how-to/this-13-inch-macbook-pro-bug-requires-8-hour-charging-to-fix/

The 2019 13-inch MacBook Pro with two Thunderbolt 3 ports) has a weird bug which requires at least 8-hour charging as part of the fix. In case your 13-inch MacBook Pro keeps shutting down, despite showing sufficient battery charge, follow the below steps to fix the issue.

This workaround has been provided by Apple on its support website. In step 5, Apples suggest charging the Mac for at least 8 hours, before updating to the latest version of macOS. This is a strange solution and is likely related to battery recalibration.