25 point in credit score can't be explained.

I was advised that I need to pay my accounts in order to get my credit score up, I paid up my accounts and sent them paid Up letters, but it was not removed from my profile a few months later I sent a dispute and they then said it would take 29 days to investigate 5 days later my score dropped 25 points, and after the 29 days was told the dispute was in my Favour, which it cnat be because my score dropped drastically, for months I have been trying to get the reason why and been calling their call center which never answers finally after 3 months I get an answer and their team leader Debbie says to me my score dropped because I paid of the account and closed it which does make sense if I paid why am I being punched and why the huge drop, and I ask her so why was I advised to pay it and she says I need to get something on credit so I can increase my score which makes sense but it's dropped to the point. That no one will give me credit so how am I supposed to get that credit to help my score and why is paying off debt being punished this makes no sense. She then says well there is nothing she can help me with so I asked for the recording but says it's a long legal process to get that recording why do they then say we must know that the calls are recorded? I think Experian scoring model is Rigged to keep certain people in bad rating. This makes no sense how paying and not having debt is bad for your credit score.