Ring the Bell
Go to Tom Nook's store with a letter that that you know has money as a present. Don't even take the present until you're inside the store. When you take it out of the envelope as a present not Bells, you should notice on the top screen where it shows how much money you have will act like it's gaining bells but reverts back to the regular amount in like a second or so. Open it and then it increases without reverting. Weird...
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