If you are using an adapter, try changing it. Faulty adapter connections will do that. If does not help, you may have a faulty card which has corrupted partition tables on it. You'll need a NAND data recovery firm to recover your data.
Here are the steps you can try:
1. Stop putting anything new on this SD card to avoid rewriting the original data, which can be unrecoverable.
2. Download a free recovery tool to your computer which has inserted your memory card with a Reader.(This free recovery program is efficient. I have ever used it to 100% recover my data from my drive. )
3. Launch it and select a practical recovery options from four. I would recommend you to select “Advanced Files Recovery”.
4. Select the SD card you want to rescue and click “Recover” in right corner to scan it for you.
5. Hook the scanned data you want to recover and click “Save Files”. You are supposed to save the recovered data in a different storage media in case of recovery failure.
6. Format the memory card.
7. Pick out the memory card as the windows allows.
I wish my words can help you a lot. Best wishes!
Thank you for the detailed answer. It is a good solution to make my card work again without any data loss.