Cant login to subsites

When I login into my main site it shows the login screen fine, see attached image.
But when I try to login to a subsite it gets all weird see attached image. Not sure what I am doing wrong please help. If I login from the admin side it is fine but if I try to login from the url:
https://ruppertmarketing.com/roofers/wp-admin/ you will see what I mean. It should look like: https://ruppertmarketing.com/wp-admin/