Help -error message when writing a post

Hi everybody,
I'm new to steamit and started writing my second blog post with images.
Always when I want to submit my written blog post an error message appears:

permlink.size() > STEEMIT_MIN_PERMLINK_LENGTH && permlink.size() < STEEMIT_MAX_PERMLINK_LENGTH:

I have no idea what this means and what I can do about it.

Does anybody know? Any hints are much appreciated! Thank You!