Hello,
1. Likely it is a known issue of the Massive Addons plugin that caused by server limits https://codecanyon.net/item/massive-addons-for-visual-composer/14429839/comments?page=36&filter=all#comment_14143143 https://codecanyon.net/item/massive-addons-for-visual-composer/14429839/comments?filter=all&page=79#comment_18501820 You need to contact hosting provider and ask to increase the maximum body length value. 2. Please check Screen Options – http://prntscr.com/rqp1hj in Appearance > Menus. If this is not what you are looking for, describe the problem in more detail and provide temporary wp-admin access.
Regards
