Empty trans unit does not display in grid

[ashish8488]

Hello,
I am using lexik/translation-bundle v3.1.1 in symfony v2.8.43.
When I am trying to load the list of translation keys in the ui (grid), it only shows me the list for which I have at least one translation value is available. If I add a new key without adding it's translation value, I am not able to see that new key in my translation list (grid). I tried to enable a feature "create_missing" that also did not work. Though in the installation and configuration guide page, it says:

"If you want to force the translations keys to appear in the grid you can enable the create_missing option."

So please look into this.
Thank You,
Ashish Shah