How do you shield your phone?
Faraday cage.
https://www.amazon.com/s?k=cell+phone+faraday+bag&i=electronics&crid=37R6OEZS3SPYE
Every microwave oven is a very good faraday cage made to keep microwaves in, but it will work just the same to keep electromagnetic waves out.
Steel file cabinet or steel toolbox will work file.