Did I can change my nickname on Betonline and can I change my Personal Information on Sportsbetting I registered a long time ago, but I'm not exactly enrolled my postal code, so that we would not rule problems?
The best place to ask that would be the Customer Service by those sites. If you go through their sites, you might even find the answer from there without even asking. There might be different rules in each site but I have an impression that changing a nickname is not easy anywhere.