Not able to make a call after clamming the phone number

Are you also dialing a US number? There are couple things you need to make a call, in your Connect instance configuration, make sure you enable outbound calling in telephony, https://docs.aws.amazon.com/connect/latest/adminguide/update-instance-settings.html#update-telephony-options and try to use a real user (not the emergency login), and in the most basic configuration, your user should belong to the Basic Routing Profile which has the Basic Queue in it. In the Routing Profile, make sure the default outbound queue setting is set to Basic Queue (https://docs.aws.amazon.com/connect/latest/adminguide/routing-profiles.html) , and open the Queue configuration and make sure to assign the DID you acquired to the Queue's Outbound Calling ID Number, https://docs.aws.amazon.com/connect/latest/adminguide/queues-callerid.html if and only if you have all these, you should be able to make an outbound call to one of the default destination like US.