Custom Map Provinces type change some sea provinces to land

[Pingulag 0]

Hello , I am asking for help

I recently started a new custom map and everything worked fine until when I maked provinces type , I set lands to -1 ans sea to -2 , fine . but when i came back to the provinces type menu 

I realised that some provinces where set to 0 , and when i modified them to -1 or -2 once again , this thing happend again , and I have no idea why (restarted the game , computer , and everything we usualy do when we encounter a bug) . If anyone find a solution , please tell me , Thanks .