I have a problem of a blocked window handle on two of the windows in my flat, so that the windows can't be properly closed nor opened, it's stuck. Some of the other residents in the building are complaining of the same issue, so it seems to be systemic (probably the top hinge, which had bent out of shape). The company that made the windows is [Content Moderated] Fixing this will probably require some specialised tools and familiarity with these windows.
Can complete for you got all tools for the job , waiting to hear from you.