The first portal I made to go to the Nether has been used for a while now. But there is a bug where if you reenter the portals in both dimensions in quick succession, it has a chance to ignore the original overworld portal and generate a new one within the 128 block radius. This is really frustrating seeing as I'm a busy player running up and down places. Discovered this bug when I changed my mind about something and wanted to head back through quickly
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Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-149705, which is a report that has not been resolved yet.
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