a750gn patch cert failed

Patch certificate started
Gathering phone info...
Collecting information. Be patient! Do NOT disconnect the phone!
Model: SM-A750GN
Sales Code: XXV
Country Code: VIETNAM
Timezone: Europe/Istanbul
Android Version: 8.0.0 [R16NW] [SDK 26]
Build Date: Thu Feb 28 16:27:49 KST 2019
PDA Version: A750GNDXU2ASB4 [february 2019, rev4]
Phone Version: A750GNDXU2ASC1 [march 2019, rev1]
CSC Version: A750GNOLM2ASB4 [february 2019, rev4]
Product Code: XXV
HIDSw Version: A750GNDXU2ASB4/A750GNOLM2ASB4/A750GNDXU2ASC1/A750GNDXU2ASB4
Board Platform: EXYNOS5
Modem Platform: SHANNON327
Serial Number: 00000000000
Imei: 354294060232486
Unique Number: CCU0021C04A4695
Connections: AT,MTP
Battery Status: 3.88V (47%)
Network Type: GSM
SIM Status: ABSENT,ABSENT
Multisim Config: DSDS
Knox Version: v30
Warranty Bit: 0
Security Patch: 2019-01-01
Data Encryption State: unencrypted
Preparing...
Checking current patchcert.
Checking modem.
Checking root.
The phone is rooted by: 19.1:MAGISKSU
Checking boot image. Be patient! Do NOT disconnect the phone!
The knox is still valid. Because of the boot patch the warranty will void.
Writing boot image.
Restarting phone.
Waiting for ADB connection. Be patient! Do NOT disconnect the phone!
Reading data...
Checking modem version.
Reading data. Be patient! Do NOT disconnect the phone!
Unable to patch certificate.
Finished at local time: [05.24.19 19:23:24]
WorkID: 60607608