Spotipo uses Stripe as the payment gateway provider. You should connect your Stripe account with Spotipo before you can start collecting payments.
Login to your Spotipo account, and navigate to Settings -> Payment ( under login-config) and click on the Connect Stripe Account button
You will be redirected to Stripe; you can just enter the email you have used while creating the Stripe account and continue.
Once you authorize Spotipo to collect payments via your Stripe account, you will be redirected back to Spotipo.
You can verify that the connection is successful by checking the status of Connect button.