I freeze in interviews, tips? after 15 years as a copywriter

I get tongue-tied when I am asked about my weaknesses. I have been trying to stay organised about it. I have practised answers but they sound stiff. Any questions to ask at the end?

Prepare three stories with a clear beginning, action and result, and adapt them to the questions.

Ask about the first ninety days. It shows you are thinking about the work.