Can't remove footer

I’ve been using this plugin with the footer embed code from AddThis with no problems for the last 6 months.

However last week I needed to remove the AddThis code so I went into the plugin and removed the code from the footer and saved. However the code still remains in the footer, I’ve even removed the ‘Insert headers and footers’ plugin but the AddThis code still remains in the footer. I am not using any caching plugins either.

How can I remove the footer code that was added?

Regards

https://www.ads-software.com/plugins/insert-headers-and-footers/