fixing issue on opencast site database

Hello, I have site: [login to view URL] I need to fix user entry, the error is that while the debase get update it create new register with same idea while it should only update exist one, keep all user update. it was working find until 2 days, something happen in each period of time this issue appear, that why I need solution, so I can fix it quick, I will need you to show me how to fix it, or create for me some function to fix this automatic. background about the site: 1. the site is only for user who his client of FOREVER company Network Marketing what is network marketing you can find here:[login to view URL] 2. the site have 3 price list, fix product to all the client group: Retail - price list 1 no discount NCP - price list 2 no discount Wholesale - price list 3 + percent discount for each user depend on his level. all of this are define my site and working fine. 3. FOREVER upload each day DATABASE file to site folder and it update 4 time a day by cron. we should take from new database each day only price list and discount if need, because this FOREVER are updating each day. I must receive all info about witch page have change and solution for the long run, I have many work on this if you are interesting this is small one :) all site function working perfectly and I want to keep it