Don't click resubmit form.

Edit: I'll be more helpful.

I think this is your connection as I do not have this issue. I think that when you resubmit your form you are resubmitting your post. The logical conclusion is that you should not click yes, as to avoid the double post. However I assume you are worried about your post not having been sent through and potentially losing your work.

So to be safe, like it says at the top of the page when submitting your post, copy your entire post to your clipboard before submitting. Another method is to just write out your posts in word or some other program. This way your work is stored elsewhere to avoid issues.

This way you can safely click 'no' on the resubmit form option, and if you find that the post did not send, you can try again easily.

Edit 2: It seems to be happening to many people actually. I haven't been around in a while, sorry about the confusion. However whenever it happens to me, this method works for me. Maybe it's different for different people.