Thank you, i found this thread, and it seems that members issue was solved:
https://vborg.vbsupport.ru/showthread.php?t=287352
"the problem was me I didn't pay attention to version numbers so I had a file that was for the update and i was still running a previous version"
Please how can i check version numbers and what files? I remember i really might put some files from other version because my site was corupted by facebook manual mod. But i dont remember which files.
// EDIT: install/upgrade.php can show it
When i run above file, it showed files i coppied from other vbulletin script version...
What i did now? Basically
i replaced /includes/functions.php with right version file from vBulletin and also whole "modcp" directory by original files (backup first). And it started working. Im sorry for my fault. i hope it helped someone save time(
--SOLVED-- peace