If you can't write to the SD card after formatting, perhaps, the SD card is write-protected, the SD card is corrupted, etc., you can try to remove write protection from the SD card, repair the SD card, and reformat the SD card to fix the read-only issue.
A memory SD card or USB flash drive has typically been set to "read-only" mode as a result of wear and tear, damage, corruption, or virus infection. Human error can occasionally render an SD card read-only. You can first try to remove write protection from SD cards in these ways:
- Slide the actual SD card lock up to unlock the SD card.
- Clean the metal connectors on your SD card.
- Disable the write protection on an SD card with third-party software.
- Delete the read-only properties from the SD card using the Command Prompt.
- Editing Windows Registry to fix SD card write protection.
In case the above methods don't work, you can run Disk Utility's First Aid to check and repair the SD card.
- Open Disk Utility from the Applications folder > Utilities.
- Click View and choose Show All Devices.
- Select the connected SD card and click First Aid on the toolbar.
- Click Run to start checking and repairing.
Now, you can try to format SD card on Mac, if it still can't format the SD card, perhaps the SD card is heavily damaged, and you can take it to a local repair for further help.