Narrow the hole.
If its a store bought one that's probably the problem. Take a small plastic soda bottle cut the end off, poke 2 holes along the side, then use plastic cable ties and attach it to the inside of the trap. The small minnows can still get out this smaller hole but not as easy.
If your interested in making cheap traps here's what I did, 1 gallon water jug cost 98「 and first time I used it I caught 20+
For more detailed info check my post #3 on this forum thread
https://www.crappie.com/crappie/live...rapping-baits/
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