Is there any way to get my old number back from an account that was inactive for some months? I'm using the same mobile phone but CS told me I needed a new sim so I did that but now I have a different number. How can I check availability of my previous number?
I definitely get preferring your old number. I would feel the same in that situation. I wish the answer was different but if the number was inactive there isn't a way to retrieve that months later. It isn't due to the SIM, we can put an old number on a new SIM, it would instead be due to us not having a way to retrieve a number once it is closed. In that situation getting you set up with a new number is the best option.