Nether portals not linking properly

On my realm I have with my friends, we are trying to link up nether portals so we have one at the world spawn, one at my base which is 300 blocks away from world spawn, one at the stronghold which is 700 blocks away from world spawn, and my friend has one that is 1200 blocks from world spawn, all in completely different directions. I have never had issues with linking up portals before but now the world spawn portal is connected to my portal which are 300 blocks away from each other and my friends portal is connected to the stronghold portal which is around 1000 blocks from his portal.