Remove database prefix

I installed and activated this plugin today and all appeared to be functioning as expected. However, I think I neglected to backup the database before enabling the prefix function, and wanted to start fresh. On the Settings page, I have used “Disable Security Features” and “Disable All Firewall Rules” and all settings reverted to original, with the exception of the database prefix.

After resetting all security and firewall settings as above, I downloaded and installed a backup of the database from a week ago, but the database prefix persists, as indicated when I access the database via phpMyAdmin in cPanel.

Could someone please advise regarding the steps necessary to remove the database prefix? Will deactivating and deleting the plugin solve the problem?

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