Dear Sagar,
It could be the issue of Aspose.Cells or Aspose.Slides. To check it if it is the bug of Aspose.Cells, simply write your generated excel on your disk and open it in MS-Excel and see if MS-Excel shows the characters garbled. If yes, then report this bug to Aspose.Cells forum.
In case, it shows right, then it means, something going wrong on Aspose.Slides side. Then attach your generated Excel in Aspose.Slides forum, so that we could fix it.
There might be another problem; perhaps the Japanese font is not installed in your machine, because Aspose.Cells might use font information from your machine etc.
Many Thanks and Kind Regards,
Shakeel Faiz
Support Developer
Aspose Sialkot Team
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