Sd card not showing on galaxy s8 plus

[Sj81]

Phone not picking up as card on galaxy s8 plus

[BandOfBrothers]

To check the card remove it and clean the contacts and re insert.

Reformat if necessary but this could delete your data.

Or as a process of elimination to see if it's the Sd card or phone at issue can you try the Sd card in another phone and another Sd card in your s8+

[Sj81]

Still don't work in phone

[BandOfBrothers]

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@Sj81 wrote:

Still don't work in phone

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Ok I appreciate it's not working in your Samsung phone. 

Is the Sd card working in another phone ?

Is another Sd card working in your Samsung ?

If you believe it's the phone at fault and not the Sd card  then I'd suggest to visit your nearest Samsung Experience Store and or Samsung Service Location.