Error writing file

I can't get to write any file on my SD card, running the bench script of Sdfat.h library I get this on serial monitor:

Use a freshly formatted SD for best performance.

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FreeStack: 568
Type is FAT32
Card size: 3.97 GB (GB = 1E9 bytes)

Manufacturer ID: 0X3
OEM ID: SD
Product: SU04G
Version: 8.0
Serial number: 0XDF112E64
Manufacturing date: 11/2015

File size 5 MB
Buffer size 512 bytes
Starting write test, please wait.

write speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
error: write failed
SD errorCode: 0X50,0X8
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