problem with framerate conversion

[Bruno999]

Hello, I have a problem using Vapoursynth to convert 29.97fps videos to 59.94 fps. The original file lasts 5 minutes and after conversion it is 20% longer, it lasts 6 minutes. This does not happen on all the files, even if they come from the same camera. The video is slowed by 20%. The encoding codec is not for nothing I try x264, x265 is the same. The original file is 9000 frames, the output file makes 21577 frames whereas it should make 18000.
Here is the debug file.
Thanks for your help I have searched but I have not found...Please, read the 'Infos needed to fix&reproduce bugs,..'-sticky before you post about a problem.