Unable to remove unused WAN connections

https://preview.redd.it/vj2mpde8eqih1.png?width=687&format=png&auto=webp&s=1e54d092242903ed0fa72e8a9bc04d6235eec8be

I want to delete WAN1 and WAN2, so I click "Manage"

https://preview.redd.it/38aowgtgeqih1.png?width=726&format=png&auto=webp&s=ede056285449ef87fe7587ee68211e7eef94168f

but the checkboxes for WAN1 and WAN2 are greyed out, I can't check them!

The only WAN connection I can check and remove is the one I want to keep!