[Sony Xperia XZ Premium Guides, News, & Discussion] noppoer2:
05-3-2018_15-50-26 ===> Flash TWRP

target reported max download size of 536870912 bytes
sending 'recovery' (21692 KB)...
OKAY [ 0.466s]
writing 'recovery'...
OKAY [ 0.000s]
finished. total time: 0.466s
05-3-2018_15-50-31 ===> Boot TWRP

downloading 'boot.img'...
OKAY [ 0.561s]
booting...
OKAY [ 5.788s]
finished. total time: 6.349s
05-3-2018_15-50-55 ===> Mount /system

error: device offline
05-3-2018_15-50-58 ===> List /system

error: more than one device/emulator
05-3-2018_15-51-01 ===> List credmgr files

error: more than one device/emulator
05-3-2018_15-51-02 ===> Remove credmgr files

error: more than one device/emulator
05-3-2018_15-51-03 ===> List credmgr files

error: more than one device/emulator
05-3-2018_15-51-04 ===> Pull system file

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-05 ===> Push system file

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-06 ===> Push lib file

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-07 ===> Push lib file

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-08 ===> Push lib file

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-09 ===> Push lib file

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-10 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-11 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-12 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-13 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-14 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-15 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-16 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-17 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-18 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-19 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-20 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-21 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-22 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-23 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-24 ===> Change file attributes

error: more than one device/emulator
05-3-2018_15-51-26 ===> Push XperiFIX Flasher

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-27 ===> Push Magisk

adb: error: failed to get feature set: more than one device/emulator
05-3-2018_15-51-28 ===> Run Xperifix Flasher

error: more than one device/emulator
05-3-2018_15-51-29 ===> Flash Magisk

error: more than one device/emulator
05-3-2018_15-51-30 ===> Wipe Cache

error: more than one device/emulator
05-3-2018_15-51-31 ===> Wipe Dalvik

error: more than one device/emulator
05-3-2018_15-51-32 ===> Reboot

error: more than one device/emulator

i got this. I have tried everything. Reinstalling the adb drivers. doing it on a fresh restarted pc. But nothing works.