>>I can´t move the blocks or boxes in some profile page
Purusothaman is right. If you can't move widgets when you are customizing only SOME profile pages, then this means that the user had added custom javascript or html code which is conflicting with the core script.
Community memebers who have previously faced this issue, have solved it by changing the theme, and then trying to customize the pages again ( if this works, just delete custom widgets added by your site users). Once you are done, you can change back to the previous theme.
>>They suddendly move somewhere else.
The Video widget did move to the left and I can´t move it to the right column.
Your site users are given the right to customize "My Profile" page, and most likely they moved those blocks.
If you don't wish your site users to customize their profiles as they wish and add custom widgets, disable this feature in admin panel>>pages&menus>>user profile page>>at the bottom of the page uncheck "Allow users to customize this page".
URL for this page is: yoursitename.com/admin/user-profile