Did you input your banking information on the square app? it will need your account number and the bank routing number so they know where to deposit the charges they process for you. This may have to be done on the website, we did it many years ago and I don't remember.
Also, if you have the contactless chip reader, you have to pair it with your phone via bluetooth. You may need to charge it first. The instructions should be in the box and there are tutotials on the app.