Why has my credit score on experian dropped 99 points?

I'm worried if someone else has taken anything else out in my name, my parents have did that to me before. When I checked my score on totally money it said I have no open accounts tho ? I'm very confused and a little concerned. How do I find out why it droped ? My credit score on experian is poor, but on... show more I'm worried if someone else has taken anything else out in my name, my parents have did that to me before. When I checked my score on totally money it said I have no open accounts tho ? I'm very confused and a little concerned. How do I find out why it droped ? My credit score on experian is poor, but on totally money it says it's 'pretty good" what do I look at? I did gets loans out myself but I paid them back on time. I pay all my bills on time etc. My score went down when my parents took stuff out but since I've told them to close all the accounts and never do it again. I'm worried if they have, if they have what do I do about it and how can I prove it was them ?
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