Turn your reference lines on.
Your walls may be touching but if the reference lines don't join then you will have your leak.
Another quick method for process of elimination would be to place a new wall at 45° angle across each corner to see if that plugs the gap.
If it does then you know which join to look at closer.
But you should be able to spot it with your reference lines on.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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