Hello Reham,
First check that you have the correct caller ID order set on the trunk

I'm assuming you're selecting the queue as "on behalf of queue" when you make the outbound call.
If the above doesn't work check the PCAP file on the outbound interaction to see if the correct CLI is sent to the service provider, it could also be them not allowing you to show the number.
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Jan Heinonen
Contact Center Specialist
GlobalConnect AB
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