Is there a limit on how much I can chat?

Yes. On Trailwise you can send Trailwise up to 30 messages in any 7 days, and on Trailwise pro up to 125. The count is rolling over the last seven days, so it frees up gradually rather than all at once. Only your own messages count: Trailwise's replies, the daily call and generating a plan are all free. When you reach the limit, the chat box is replaced by a note with the exact day and time your next message opens up. See Plans.