Wrong Eye of Ender direction

I deleted the chunk files (server\world\region\r.0.0.mca, etc.), beacuse i would have like to prepare a new region in everywhere (except in my homeland), and later i dropped an Eye of Ender to find a stronghold. I went to location where the eye directed, and dug out the entire area. The eye just hovered in the air, where there was nothing. I revealed all of the area, but I did not find the stronghold.

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  Seed: -644880586686743976
  Coord x: 747, z: 87