The list owner or LISTSERV postmaster needs to send the command
 
FREE xxxx-L
 
to LISTSERV in order to free the list.  What this means is that the
list has exceeded the Daily-Threshold limit, which by default is 50
messages/day.  The default can be raised by adding the line
 
* Daily-Threshold= xxx
 
to the list header, where xxx is the number of messages/day to be allowed
through before the list is held.
 
Nathan