only official released binaries are allowed to be flashed

Patch certificate started
Gathering phone info...
Collecting information. Be patient! Do NOT disconnect the phone!
Model: SM-G955F
Sales Code: DBT
Country Code: Germany
Timezone: Asia/Dhaka
Android Version: 8.0.0 [R16NW] [SDK 26]
Build Date: Tue Dec 4 12:07:47 KST 2018
PDA Version: G955FXXU4CRL3 [december 2018, rev3]
Phone Version: G955FXXU4CRKB [november 2018, revB]
CSC Version: G955FOXM4CRL1 [december 2018, rev1]
Product Code: DBT
HIDSw Version: G955FXXU4CRL3/G955FOXM4CRL1/G955FXXU4CRKB/G955FXXU4CRL3
Board Platform: EXYNOS5
Modem Platform: SHANNON355
Serial Number: R58J54LM7KZ
Imei: 3587920882xxxx
Unique Number: CE041714809F540C02
Connections: AT,MTP
Battery Status: 3.86V (61%)
Network Type: GSM
SIM Status: ABSENT
Multisim Config: SS
Knox Version: v30
Warranty Bit: 1
Security Patch: 2018-12-01
Data Encryption State: encrypted
Preparing...
Checking current patchcert.
Checking modem.
Checking root.
Checking custom root image...
Present.
Rooting by custom image-based root method...
Flashing firmware...
Switching to download mode.
Waiting for download mode.
Connecting.
SBL Info: Model: SM-G955F, Region: EUR, Provider: OPEN, PDA: G955FXXU4CRL3
Reading PIT from phone.
Flashing boot.img
Firmware flash failed.
Finished at local time: [03.12.19 21:27:38]
WorkID: 54572441


FRP OFF
OEM OFF