All strings in dll file are deleted accidentically in Passolo 2015

Version Information
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Passolo Team Edition 2015
Version 15.1.465.0

Windows 7 Service Pack 1

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Description

When udpating all strings lists in LPU, all the strings in 2 dll files are deleted accidentically but actually there is nothing update in the 2 dll files. The dll parser is dotnet parser. After restarting Passolo application, and update the 2 dll files again, these deleted strings are added in LPU again. It's very strange. I can't reproduce this issue now. Could anybody help check this issue and let me know the root cause?