object invalid value

Hello,
I have the same problem as someone here.
sometimes it works, sometimes not.
the whole process runs off, if it does not work:

I write something, then comes the message: “object invalid value”
I can then do nothing more and the post is then only on my side to read.
I would like to delete this post, then it does not work. I must first leave the post – open again, then I can delete the post.
when I write the same again, it works immediately.

sometimes it works the first time.
I’ve already disabled many other plugins, deleted everything
  tried – but it is always the same.

I can not delete everything, just so this plugin works ??
I like the plugin very much – I love it !!
but these problems are very bad!

greetings,
Jürgen

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