Bootloader seemes to be unlocked but cannot flash using fastboot

Hi,

First of all sorry for crappy links, but as a new user I cannot post them.

I have got a chinese phone called Haier W858 (imei.info/phonedatabase/15302-haier-w858/). Few days ago I found out that it is similar to Smartfren Andromax I3S and managed to modify stock ROM by fastboot without any problems (current ROM: needrom.com/download/smartfren-andromax-ad682h/). After that when I tried to turn on fastboot mode I got information that bootloader is locked and I need verify.zip file on sdcard to unlock it. Few searches later I found correct verify.zip file and put it on sdcard. Everything should be great, because now when I try to run fastboot mode I get information that verify.zip file is correct and phone turns into some kind of fastboot mode, but I cannot write anything to it.

For example, I get messages like:

Code:

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> fastboot flash modem modem\NON-HLOS.bin
sending 'modem' (31985 KB)... OKAY
writing 'modem'... FAILED (remote: can't flash Partition)

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When I check if bootloader is unlocked by fastboot oem device-info I get:

Code:

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>fastboot oem device-info
... INFO        Device tampered: true
INFO    Device unlocked: true
INFO    Charger screen enabled: true
OKAY

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so it looks like everything should be alright.

Whatsmore, I can write any ROM by doing it like so:
- turn into that weird fastboot mode,
- boot up into TWRP or CWM by writing: fastboot boot recovery.img (because of this problem I cannot flash it permanently so I boot it up),
- install ROM from recovery.

What my question is - is it possible to flash previous fastboot mode where I could write anything to phone without problems and without checking any verify.zip file?

I do not know if it could help in anything but this is shot made when I did not have correct verify.zip file: postimg.org/image/u7thz6tq7/. Now it says that it is OK and boots up into that weird fastboot mode.

Thanks in advance.