FlatFile convertToValues get error Variable Length file format invalid

Hi,

I’m using Integration server 10.15 and WmFlatFile version FlatFile_10.7_Fix13.

I’m using pub.flatFile:convertToValues with variable length and get error “java.io.IOException: [FFP.0014.0003] Variable Length file format invalid, file ended before record filled”.

My format flatfile like this:
Value1Value2Value3
Value1Value2Value3
Value1Value2Value3

And sample string like this:
1012Testuser10123101
2212Testuser20123202
3013Testuser30123303

My screenshot flatfile and flow service like this:

How to fix this error Variable Length file format invalid?

Thanks

Seems this same error was encountered by others earlier but no Conclusive Answers.