SD card issue, need a format, losing my data on it

Do you have Linux ? Have you inspected the card with Gparted ? If no to both, do you have experience of booting a distro from CD ? If you have no Linux, Gparted is available as an .iso. https://gparted.org/livecd.php.

The reason I ask is to try to see if the card is already in less than perfect condition as measured by a standard Linux system.

I guess you already did, but it is probably also worth checking if the micro SD card specification is within that specified for the phone.

I guess it is this card: Can't use my SD card as I would like to. Often it is advised to format a card on the device; however to undo the effect of being in adoptable storage when I had that issue I wanted to format it on a PC, even allowing for the fact that I might reduce its overall length of life. I also ensured that the phone worked fine with a different card before returning to the newly formatted card.

As this 128G card may be quite valuable I might buy a small best quality card to see that the phone behaves fine with that for a while.


Edit, I notice you describe the card as 128G but also 150G elsewhere. If the card has any indications of being ambiguous about its actual size I would treat this as being a defect.

Further if you have evidence that the card cannot keep up with good performance (I think you have previously observed poor photo results) it may be the wrong card for your intended use. This could be investigated further with a new smaller “best” SD card.