1. Please make sure the circled little metal switch is touched with the SD card after you inserted in the card. 
If it's not, you can adjust the back metal piece by tweezers so that it can tightly hold the little switch and thus make them touched. 
2. Pls try to add 1-2 layers of tape on this side of the microSD card:
3. Try to format your microSD card following this article:
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