SDcard not visible under android 5.1

Hello,
i bought a teclast X98 pro... But i think this issue could be the same on X98.

Under windows my SDcards are all fine...
In Android 5.1 i cant see my ext sdcard. I tried different SDcard sizes and partition formats ( fat, exfat)
i cant get it run... In the settings i see one SD card (disabled, means grey options)
Four USB-storages (disabled, means grey options)
I think this could be normal for all the windows partitions right ?
But how can i get my external SDcard to run ? For now i use Sandisk Ultra 16gb. Work fine in different phones and tablets and on the tablet i Windows 10.
I resetet the tablet to factory ... it didnt helped... But at the first startup i saw a message that the sd card was propably ejected out from the device... I didnt touch the device at startup...
Like i said before, in windows all works fine with a Sandisk 128 gb without problems...
I searched but didnt found anything...

Maybe anyone can help me with a good advice ?

thanks a lot for any help.
Cargoman

Samsung fixed my "water damaged" Note5 under warranty

Previously..

9/24/2015 11:52 AM-PBA Inspection: The unit has left the technician. SOLUTION: BER
*09/24/2015//12:52:10//000*******//Telephone//ASC*
Liquid damaged on PBA components


The latest..

*10/09/2015//11:28:17//000*******//Telephone//ASC*
10/9/2015 10:27 AM-***** ******: The unit has left the technician. SOLUTION: Replaced Component - Replaced PBA

In the end, Samsung agreed with me.

If you want to know what happened you'll have to find the other web board (one that doesn't have itchy thread lock trigger fingers) I posted the story to.

Thanks for fixing my Phone under warranty Samsung..