Can't resolve dependencies on startup

[simple beacon]

Please make sure that the argument dependency
This is most likely a circular dependency between two classes. Can you show the AuthService?

[slate epoch]

The most common error in Nest is failing to resolve provider dependencies.
The error message usually looks something like this:

Nest can't resolve dependencies of the <provider> (?). Please make sure that the argument <unknown_token> at index [<index>] is available in the <module> context.

Potential solutions:
- Is <module> a valid NestJS module?
- If <unknown_token> is a provider, is it part of the current <module>?
- If <unknown_token> is exported from a separate @Module, is that module imported within <module>?
  @Module({
    imports: [ /* the Module containing <unknown_token> */ ]
  })

The most common culprit of the error, is not having the <provider> in the module's providers array.
Please make sure that the provider is indeed in the providers array and following standard NestJS provider practices.

There are a few gotchas, that are common. One is putting a provider in an imports array.
If this is the case, the error will have the provider's name where <module> should be.

[simple beacon]

Oh, you have @Inject() without specifying an injection token. Why is that?