Did almost everything I can do, nothing seems to fix the problem. Sometimes I can get into the game, play just fine, however when it's starting to load something like file,images etc. It'll stuck and then turn into black screen.

Honestly, when my network was so slow it works fine despite disconnected from the game a lot of times, still playable and still load files from server. However this case might be different, my network works just fine no problem whatsoever but load nothing out of the server. The server might be faulty or busy