how to delete lingQs in the new system?
To remove a LingQ, just click the red “X” on the status bar in the LingQ widget.
There may be multiple ways, but if you go to your Vocabulary page, viewing the “All LingQs” tab (which is the default), you can check the LingQ(s) you want to delete. Then under “More Actions” you can find the Delete action. That should delete the LingQ. Only available if you have a non-free account.
I have a problem to say in my acount if I need of the premium acount
As a paying member, you can update the status of your LingQs or delete them anywhere that the status bar appears (on the Flashcards, the yellow popup, the vocabulary page, the LingQ widget, etc.).
As a free member, you will only be able to update the status or delete a LingQ using the status bar on the LingQ widget (when you click “Edit LingQ” on a yellow popup, for example).