As far as I know you can only change your number by porting a number over to 48 from another mobile provider.
You might want to contact 48 support in case they can assist with this.
But it's quite possible that the number that you want is used by someone else and no longer available in any case.
See the links in my signature below.
BTW it's not really a good idea to post personal details such as your phone numbers in a public forum like this where anybody can see and use them.
You might want to edit your post to remove them.
