This drive won’t mount without running some kind of disk repair utility and it takes a long time to copy data!
Response from SanDiskBy SM OLS Team, September 27, 2022
Hello,
I am Will from SanDisk® Global Support Team. The speed of a Memory Card depends upon various factors. The interface used to connect the card to the computer may limit the speed of the card as well. However, in order to isolate the possibilities of the issue that you are facing we may have to perform a speed test on your Memory Card to check if it is performing within the expected specifications. SanDisk® stands behind its commitment to quality and warranty on its products. We will also check if your Memory Card is eligible for a possible replacement. I would suggest you to please contact SanDisk® support at 1-866-SANDISK and we will isolate the issue and will assist you towards a resolution.