If you're seeing a discrepancy between the number of derogatory marks under your "Credit factors" section and your "Derogatory marks" section, the likely explanation is that you do have a derogatory mark on your credit report, but that it's related to a closed account.
Here’s how to view these accounts:
1. From the nine-dot menu in the top right corner, click Credit Score
2. Scroll down to click on See my full credit report
3. Scroll down to the Your accounts section
4. Click the small blue Show closed accounts link, found just under your open accounts
Once you've paid off and closed an account, it still appears on your credit report and can impact your credit score. This NerdWallet resource includes more details about this: Why Are Accounts That Have Been Paid Off Still on My Credit Report?