In Minecraft Nintendo Switch there is a bug where If you make two Nether Portals, and you go in the second one you made, it leads to the exact same spawn as the first portal, and if you go out of the nether using the portal you came in with, you will be with your first portal, not the one you just used.
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migrated
Duplicate of MCPE-39609, which is working as intended. You can read the description of that ticket to understand how nether portals work.