Translating sequences is not included in the File Format Conversion section of the Utilities, for this step , you will have to go to another section (Alignment Utilities) and use the CDS-ProtAl utility.
Go to the Utilities page and in the Alignment Utilities click on the CDS-ProtAl link.
If you have saved your recently converted file on your computer, you can upload it from your machine, or, if do not have saved it just select the file from the server, in the job generated data.
Just check “translate” and run the job (for this example you can just let the default Genetic code). This time, only one file appears, it corresponds to the translation of your sequences. Note that under this mode CDS-ProtAl is not trying to align your sequences.