Angular 19: NullInjectorError: No provider for _ResetGuard when navigating to...

I'm trying to debug a puzzling issue in our Angular 19 application that occurs during navigation to a recently added route /reset-confirm. The error we're getting is:

NullInjectorError: R3InjectorError(AppModule)[_ResetGuard -> _ResetGuard -> _ResetGuard]:
NullInjectorError: No provider for _ResetGuard!


Here's a step-by-step account of what I've implemented, what works, what changed, and where it broke.

Initial Setup and Working Components -

• 
  We have an authentication flow that includes SignInComponent, SignUpComponent, and VerifyComponent.
  
  
• 
  These components are wired up through Angular routing.
  
  
• 
  Access to /verify is protected using a VerifyGuard, which checks for sessionStorage entries and query parameters.
  
  
• 
  This entire flow works as expected and has passed QA.
  
  
• 
  These components are added to the AuthModule and are included in its imports array.
  

New Components and Logic We introduced two new components:

ForgotPasswordComponent – After a successful email send, it sets a sessionStorage key and navigates to /reset-confirmation using a custom RouterService.

ResetConfirmationComponent – This component’s ngOnInit() checks for a sessionStorage value and query parameters to confirm access is valid. If not, it redirects the user to /login.

The Problem

When navigating to /reset-confirmation from ForgotPasswordComponent, we get the NullInjectorError

Here’s what’s confusing:

We do not have any guard named ResetGuard or _ResetGuard in the current codebase.

We did have a ResetGuard previously but removed it — including removing it from all routes and providers.

This error does not occur locally, only in staging builds.

In app.config.ts, we define our routes using provideRouter(routes):

export const appRoutes: Routes = [
{ path: 'login', component: SignInComponent },
{ path: 'sign-up', component: SignUpComponent },
{ path: 'verify', component: VerifyComponent, canActivate: [VerifyGuard] },
];


All the components are standalone.

I need serious help in this.

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