Amazon Web Service (AWS): Spot request active followed by cancelled terminating
Seems like the initial limit for instances is set to 1. Solution is to request a limit increase which is not intuitive by the provided instance cancellation.

AWS Service Limits


  You can take the following steps to request an increase for limits.
  These increases are not granted immediately, so it may take a couple
  of days for your increase to become effective.
  
  To request a limit increase
  
  Open the AWS Support Center page, sign in if necessary, and choose
  Create Case.
  
  For Regarding, choose Service Limit Increase.
  
  Complete Limit Type, Use Case Description, and Contact method. If this
  request is urgent, choose Phone as the method of contact instead of
  Web.
  
  Choose Submit.