I am trying to restore wallet from 12 word seed, but when i enter the seed the Next button remains unlclickable.
Generally that means you've typed the seed in wrong? Is it definitely 12 words cas it's fairly easy to miss one off somewhere...
If you try to reinstall electrum, see if the same thing happens. Also the words are supposed to make sense in English, so you could test that to ensure that words have been reproduced correctly.