By default, Prestashop will force you to change your admin URL in which it may not be admin123. Softaculous may name it admin123 for you if you do not change it, but it can be anything that you want it to be. I do see it here in your acount, however, I cannot give any specific information as to what it is named over this public forum for your security. If you are still unable to locate it under a different folder name, you may also contact technical support to help you locate it.