How to use translation:update in symfony2?

I have some bundles in a Symfony2 project and I'm running the "translation:update" command to update the translation file for my bundle. While most of the parts works well and get the appropriate names, I don't seem to do the same for the form fields in the view files. Every time I run the command, I get back only the field name and not the full path I want them to have. For example e.g. I get fieldname instead of Mybyndle.formlabel.fieldname. I use the label option in the form builder in order for them to have the appropriate name as key and indeed the name changes when I see the form. But when I update the translation file, the entry in the file is only the field name.

What should I add to my code so that the translation sequence uses the correct format?