Steps to recreate glitch.
-Create first portal (portal A for overworld side, portal B
For netherworld side ).

-Go back to overworld and move to a place beyond the 128 block radius described in the wiki.

-Create a new nether portal (portal C).

Instead of creating a new portal in the nether it takes you back to portal B. If you then use portal B instead of taking you to portal A it creates portal D in a location near portal A.

If however you create portal C in the nether, it creates a portal at the proper location in the overworld.

This issue keeps on being dismissed, but I assure you there is something wrong with creating Overwold to nether portals, but not nether to overworld portals. It is not following the rules described in the wiki.