A .pls file is a playlist, hence not actual audio file. It is just a list of audio files that should be played in certain order. As such, there is no way how you could convert pls to wma.
At best, you can open the playlist with a text editor and check the locations of the actual media files.
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
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