Shanko,
People who have posted two or less messages on RootsChat ('RootsChat Pioneers') have their inbox on RootsChat personal messages restricted to twenty messages. If they delete older messages to make room then they can continue receiving personal messages.
Users who are active on RootsChat, or should I say, those who have posted more than two messages do not have this restriction.
If you send me the username of the person (by personal message) you are trying to contact, then I will see if we can make contact with them.
Trystan