How Do You Know if Someone's Asking You to Send Money Back?

If someone's asking you to send money back, that is the weirdest yankee stuff ihave ever heard of, right? It would deftinitly raise some red flags. My question, i'd like to find this out from a bank. But way, this is me hating on banks, but wai longer than it should. That check should be discovered the moment it walks in there. And you get charged if it turns out to be bogus. I they, the bank will charge you for even trying to put it through. Not to mention the overdraft, stuff it with all your other stuff, that will bounce too. Because money never goes the other way, never.