The S9/S9+ features a concept change on proactive maintenance concerning microSD card failure.
Because microSD cards have a limited lifespan, it is important that customers be notified when the microSD card may be failing or causing performance draining behaviors. The S9/S9+ monitor the health of the microSD card and will notify the customer if errors are occurring because of the memory card.
Note: If the error consistently appears on the device, the customer may need to format or replace the memory card.
For best results, Samsung strongly recommends customers use Class 10 or newer memory cards on their device.