If you see a notification that says Storage in This Mac Needs Service
Back up your Mac and schedule a service if you see a notification that says a serious error with the SSD has been detected.
The SSD (solid-state drive) in your Mac includes SMART (Self-Monitoring, Analysis and Reporting Technology) hardware. This technology detects blocks of flash memory that have stopped working correctly. If your Mac detects an increased number of bad memory blocks in the SSD, a notification that "Storage in This Mac Needs Service" will appear.
Receive a service for your SSD
Back up as much of the data on your SSD as possible, then contact Apple Support or take your Mac to an Apple Store, Apple Authorised Service Provider or an Independent Repair Provider. Genuine Apple parts are also available for out-of-warranty repairs through Self Service Repair.