[galaxy-dev] FASTQ converter not working

So I have used Galaxy to convert >50 different FASTQ files into FASTA with no problems before over the past year. The sequencer and FASTQ file format have been identical, however, yesterday when I tired to use the the FASTQ to FASTA converter I couldn't get it to recognise my files. The drop down 'FASTQ Library to convert:' tab was empty and unable to select the dataset to convert I then switched histories to one where this action had already been done to repeat it and make sure it was nothing odd with the file I uploaded. However, again the tab was empty and I was unable to select the file to convert. Suggestions? JT