how do I connect a province to the sea?

[MonterosJose 0]

I have the problem that the mod that I downloaded (and that happens in the original game) is that some provinces attached to the sea can not go by sea, and I was looking and the other provinces are at 0, while those that do not work are at -1.

Here the examples:

and sincerely I am years trying to fix it, but I never knew how, could you help me how to connect? (and if you tell me to connect as if it were normal, it does not work, as you saw in the image they have special lines, if I connect as if it were a province, it appears with lines).

here the example:

Thanks you

[Pvc 0]

Well I don't know if it will work but, first remove the connections with the seas and lakes from the terrestrial province, then set the terrestrial province to -1, after that connect the seas and lakes to the province and according to what I tried with my map and from what i remember, it should be set to 1 and you could build ports