I have a problem with MC11000 the top thread does catch the bottom thread and then a nest of threads is formed.

I see you have your answer. Just a flower for you

UNTHREAD IT, then clean out thread path with unwaxed dental floss, clean out bobbin area, change needle, then re-thread. make sure you are threading the upper area correctly, open the side door and take a peek at the thread path. make sure, then start again.