RP-AC68U USBkey in Ext2/3 Mount Size Problem

[agodng]

Hi, another problem with this RP-AC68U Repeater, note that it is up to date with the latest official firmware

If I put a USBKey in the USB3.0 port (16Gb SanDisk) formatted in NTFS or FAT32 is mounted properly correct, and after I can use samba shares or download master ecc perfect


The problem is when the key is formatted in Ext2 or Ext3, this is mounted but the size is only 3.0M

I tried to format key from last Ubuntu and after from the device with telnet

first:
- I created the primary partition
fdisk /dev/sda
:n
: p
:1
:w

second:
i formatted in ext2
- mkfs.ext2 /dev/sda1 -L MyLabel

format finish ok
then reboot device
sda1 is auto mounted but have only 3.0M

I try 2 usb key and always the same problem, in NTFS or FAT32 no problem..

why