Here is a screenshot of the problem:
According to your picture, your standard Chat tab has been moved to the top-right. Click on that to see your Team chat displayed again. Since there is no other tab in the lower half, the dividing line was removed. To get the Chat tab back down to a lower-half, Right click on the Chat tab and click "Move to Bottom".
Alternately, log onto a character that has the chat tabs set up the way you like them and type /chatsave, then log back onto the affected character(s) and type /chatload.
That worked, thanks a million, it has been irritating me for a long time
Sometimes, when I click too much and there is too much action going on, my chat window changes. Instead of two halves (of adjustable size) the lower half diminishes to just one line and the upper half is the only one that can be adjusted.
Is this a known error? What must I do to change it back?
It has happened to me on two lvl 40+ toons, but only on them, so it must be quite rare. It seriously disrupts my game. Right now I can't see team chat at all
What to do?