m250 flash problem - frp downgrade

hello
i tried downgrade firmware to frp reset:


Welcome to Octoplus/Octopus Box LG Software version 2.8.9

Checking data...OK
Platform: LG MTK
Selected port: COM340
Selected baudrate: 921600
Selected model: M250N
Selected USB connection type
Please, disconnect cable, reconnect battery, connect P999 cable (with
910k resistor)
or
Reconnect battery, press and hold "Vol+" for 10 seconds and connect
Micro USB cable.
Phone found at port COM340
Mode: Emergency
Initializing flash...OK
Model ID: LG-M250n
Platform: mt6750
Android version: 8.1.0
SW version: LGM250nAT-00-V20b-EUR-XX-AUG-13-2018+0
LAF Version: 1.1
Product ID: CY12S171009006168
IMEI: 354945-08-597899-5
Target operator: GLOBAL
Hardware: rev_10
Battery level: 72%
Reading partitions...
Performed by 2.8.9 Software version.