Server administrator changed chmods to 775 for folders and 664 for files and for now it’s working. He also placed me in the group.
The thing is earlier i get root permission on ftp user but not on www-data user. Now we’re both in same group. Maybe it depends on hosting. Anyway, wordpress itself doesn’t need 775/664 (needs only 755/644) but ML+ need it.
Thanks for everything!