It is probable that they gave you, literally, instructions on moving those Sony e-book files, but not how to make them useful once they were moved to a Kindle.
The format for Sony e-books is too different for a Kindle to even see them (apparently) as such.
So converting them with a file converter, on your PC, before so moving them to the Kindle device, might have a better result.
If you would like to try that, please tell me what one of the Sony e-book files on your computer is:
1. in point of its full file name, including extension, and/or
2. its File Type in its right-click Properties, see the File Type listed on the General tab of the file's Properties.
Let me know, if you'd like to try that, and I will attempt to find a converter you can try using on the Sony e-book files to make them readable once so converted and moved onto a Kindle / your Kindle device.
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