Hello,
I also have this problem on my project. It worked before, and now it doens't work.
I also saw another guy getting the same problem as me 1 week ago.
I tryed using the last version of plugins, and I tryed by de-activating all scripts & plugins too. (I'm not using a theme, but oxygen builder).
When an user (or admin) send a frontend submission, some fields are missing : All for subscriber role. (terms, and custom fields like text, but not images)
For admin : some texts, but not all, and term all the time.
Do you want to have an access to my web, to see by yourself?