Hey Giora,
I am sorry for the delay of this reply,
I've applied some fix in these 2 files in your site,
JoomlaFolder\administrator\components\com_easyblog\includes\router.php
JoomlaFolder\components\com_easyblog\includes\router.php
Can you try submit a new blog post and see how it goes?
If the issue still persists, can you provide us with your Superadmin backend access so we can help you check on this? Because I've tried to login in your joomla backend, but it seems like you already changed that user account password, please advise.