Unable to deactivate and reset

Due to my try to made Cloudflare work I discover now I’m unable to deactivate the plugin because do this generate a WordPress fatal error and the plugin is not deactivated. I can rename the plugin folder and remove but when I reinstall all settings are back and I’m unable to also reset the plugin as the button doesn’t nothing.

Could you please provide the step to remove and reset the plugin manually?

Thank you

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