Task: Question Decomposition
Input (English): question: Which customers have used both the service named "Close a policy" and the service named "Upgrade a policy"? Give me the customer names.
Output (English): #1 return services 
#2 return #1 that are named  Close a policy 
#3 return #1 that are named  Upgrade a policy 
#4 return customers of both #2 and  #3 
#5 return names of #4