Help Fix Bad Value

Hello,
Does anyone know how to fix the following?
Thanks
Line 168: Bad value “https://api.w.org/” for attribute “rel” on element “link”: The string “https://api.w.org/” is not a registered keyword.

ugin/ –> <link rel=’https://api.w.org/’ href=’https://www.tgfsecurity.co.uk/wp-json/’ /> <link