Cannot change vaultwarden port

I tried docker run port 8080:80
It keeps running on port 80.
I don’t know why and i don’t know how to change it

What do you mean? Did you restart the container?

Inside the container it runs on port 80 because ROCKET_PORT=80 is set by default. If you want to change that you will have to set this environment variable yourself (and adapt any published ports accordingly).

How can i change it? Where is that file?

That depends on your deployment method. So you probably want to start with:

You might get a more helpful answer if you tell us what you want to achieve by changing the port.