S20 FE

[AJ27]

My wife is having problems where after a few minutes of inserting the tray with the SD card there phone says it can't read it. 

Any solutions?

Tried a couple of times of removing the card and making sure it's mounted properly but to no avail. 

[Jayman1973]

Here are some suggestions that might work:
1) Has the SD Card been formatted for use in the phone?
2) Do you have another Samsung phone that you could test the SD Card in to see if the card works?
3) Try turning the phone off, remove the SD Card, wait 5 to 10 seconds, re-insert the SD Card, turn the phone back on and see if the SD Card is accepted.
If by chance these suggestions do not work, then the SD Card may be defective.

[AJ27]

The card is transferred from her S9

[RedDogRabbit]

If you tried all of @jayman1973's suggestions & you still have problems, you could try inserting the sd card into a pc adapter & scan it for errors with Windows. There should also be a "scan & repair" option.

[Georgine]

Hi, please try the suggestions provided by others and check if the issue still persists.

[AJ27]

It turns out the card was near capacity.
Thanks for all the help.