Hello! What's the specification of your servo? If you can add the link of the exact unit you purchased that would be great.
There are some reasons why you may be facing this issue e.g. you purchased a 360-degree servo, a servo that requires more current, or some other component in your build is sucking up the current etc.
My suggestion would be to test the servo on its own (linked to your Arduino) and run a simple 180-degree spin code to see if it does the simplest of tasks.