Unable to use rand crate

I’m unable to use the rand crate in the Rust track exercises, even though it is on the list of approved external crates. When I submit a solution to the Diffie-Hellman exercise that uses the rand crate to initialize the private key, the tests fail with the error

use of undeclared crate or module `rand`

You added the crate to your Cargo.toml file? Could there be a version discrepancy?

If you’re using the command line, did you upload your Cargo.toml too? exercism submit foo.rs Cargo.toml. I regularly forget and then get errors.