It turns out British Raj deleted all their ports.
Yeah as it is currently the AI will destroy all its port in case of budget problem, since they are expensive to maintain and provide indirect benefits. The problem is, as soon as they will be able to afford it, they will spam a ludicrous amount of ports, building only that and most likely drive them to another budget crisis, and the wheel keeps turning. Even if they manage to not ruin themsleves with ports, the next war will, and they will destroy them.
I like this example a lot: I took a Russian Alaska that had 15 ports built and 0 gold mine (on a max of 12)... After winning a war against against the US, I noticed they were much more hurt than they should be (I only took a couple of great plain underpopulated states) and switched to it to check what was going on. Because of the cost of the war, they had destroyed all their ports, killing all their trade, and where in the process to rebuild them, 3 pages of queued ports with a pitiful amount of construction points. It goes without saying they never recovered...
The only "fix" so far is using Anbeeld AI mod.