Other starting from scratch with 48 (new email address/account/SIM etc.) in order to get a different random 089 number:
the only other way is to get another number/SIM from another provider and then port it over to 48 to replace your current number.
What exactly do you not like about your number?
Seems like an odd complaint.
Most people want to keep their number because it's how others know how to contact them.