Strange tie problem

[Haipeng Hu]

Hello,
  I just completed an 8-minute orchestral piece for an activity. All
are ok, except the passage for trombone attached. This is part of the
second theme of sonata form, and the log file says there's an
unterminated tie. But the tie is in the same voice, with correct pitch
tied. I don't know whether the tie shows correctly in print, but why
Lilypond generates such a strange warning?

Regards
Haipeng

trombones.ly
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