When someone robs a bank and makes off with cash in the bank that money will still be with the robber until they're found.
The money is eventually all made useless to the robber because they'll be a die that is put in with the money that sets off after a certain amount of time which then marks the money and can get on the persons hand who robbed it.
Your money is insured by the FDIC so you'll be protected for your money if the bank gets robbed.
Your money that you deposit into the bank is usually not at the bank anyway since it's sent off and invested in stocks, bonds and even loaned out to other people.
But even though your money is invested and loaned out you can still pull cash from your bank account and use those funds because they draw the money off their account to give to you.