I keep a fine mesh filter handy when it does happen. Then I just pour the pot into another air pt through the filter. You lose some temperature, but not enough to chock it up as waste. Most of the time I'll just really make sure I press the filter in the edge...or tuck it into the wire. If its a little wet on the inside, it helps it stick better too. And being gentle and putting the basket in level really helps. You could also tweak your grind. Sometimes if the grind is too fine the basket seep rate will be to slow, and overflow.
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