Pretty much what has already been said plus the possibility that someone accidentally blocked someone. I've accidentally clicked on things before without realizing it. Might explain those random non-contact blocks.
Being blocked
First of all, please tell me you do a better job of spelling words correctly in your initial contacts than you've done here. Like, not judging, but properly spelt introductions are pretty important. Second, yeah, sometimes people will block you, not because you've done anything wrong, but because you're not their jam and they're being efficient in insuring you don't show up in each other's searches anymore. Finally, yes, men do generally run the couples profiles and, no, there's nothing wrong with that. A couple's decision wouldn't change if you somehow reached the woman instead, because they're in this together and a) he probably already knows what she likes, and, b) you have to appeal to both of them, even though you're only having sex with one of them.
I've heard that some people block because they aren't interested and don't want to see you profile every time they do a search. They are pretty much using the block function instead of notes.
Some people block if they don't want to see your posts in the forums - often happens to profiles that spew nonsense or offensive drivel.
And others block for no apparent reason - we've been blocked by two different couples that are several states away, that I've never had contact with and have no reason for contacting since we play with single guys.
I wouldn't worry as long as you are friendly and courteous in your approach to others.
Some people will block if they're not interested. Sometimes there is no other reason. The only reason I will block someone after they email is if they're disrespectful, or if they keep emailing after we've said we aren't interested.

