u/IcyBed2421

I'm playing as the US and having to go to war with Mexico. I have a Marine force going to do a naval invasion. I have one navy patrolling the Caribbean, but when I send another Navy that's stationed in eastern Texas, but when I send them to patrol the Gulf of Mexico, it says that there's no accessible region. Is there anything I'm doing wrong or is it a bug, I'd hate to have to stop the gameplay because of it.