If you have tried all the troubleshooting steps and the SD card still doesn't show up on your Mac, consider the following options:
Test the SD card on a different computer or device to ensure it's functioning correctly.
Try using a different SD card or SD card reader on your Mac to rule out any hardware issues.
Contact Apple Support or visit an authorized service provider for further assistance. They can diagnose the problem and provide a solution or repair if necessary.
If the data on the SD card is crucial, you might consider contacting a professional data recovery service to retrieve the files.