Link blocked on only groups

i have juste started a website and while i was testing it i faced a quite strange problem .
When i wanted to share it on one of my groups , it says "

Group Post Failure

The message could not be posted to the group. "

I can share the website on my wall or on any page or comment , but when coming to the groups it couldn't be shared

Update :
I Have the same problem with a new site i just created , i can however share posts only directy from my share button on my site . When i try to share the links on my wall or on any of my pages i get Image verification capctha !
Anyone facing that problem ?

Yeah, facebook block new domains really fast if he think it's a spam.
I suggest you to buy 100+ new domains, make 301 redirect and make spinax with them in posts.
It should work for some time