Cash register data conflicting

Hello i have setup 3 computers for my business. I have installed aronium pro on Pc 1(Thats my database server), Pc 2 and 3 as my cash registers respectively. When i add products for Pc 1, it also shows in Pc 2. Floor plans as well. How can i make the exlusive to each other? So i can manage them on my Pc 1. NB. I always make sure to select the the cash register in the database. And also when optimizing databases on Pc 2 and Pc 3, i get the feedback Pc1/guest login not found, same for Pc 3 as well. Pc 1 optimizes perfectly. Can you assist? I'm really keen on making this my business POS. Side note i Just started. Thanks