Laravel 6 - Route post not found

I'm trying to implement Register User in NuxtJS. However, I'm having this issue like below

vendor/laravel/framework/src/Illuminate/Routing/RouteCollection.php

In My api Route

 Route::post('register', 'V1\Auth\LoginController@register');

I'm try change it to get method and access it by 127.0.0.1:8000/api/register its work pretty fine.

i still have no idea, why i got this POST http://127.0.0.1:3000/api/register 404 (Not Found)

In My Nuxtjs

           async registerUser() {
                try {
                    await this.$axios.post(`api/register`, this.auth);
                    await this.$auth.login({
                        data: {
                            email: this.auth.email,
                            password: this.auth.password,
                        }
                    })
                    .then(res => {
                        console.log(res);
                        this.loading = false
                        // this.$router.push(`/auth/login`);
                    })
                    .catch(err => {
                        this.loading = false
                        this.$refs.form.validate(err.response.data.errors)
                        console.log(err.response);
                    })
                } catch(e) {
                    // statements
                    console.log(e);
                }

In My Controller

    public function register(Request $request)
    {
        $request->validate([
            'name' => 'required',
            'email' => 'required|email',
            'password' => 'required|between:6, 25',
        ]);

        $user = new User();
        $user->name = $request->name;
        $user->email = $request->email;
        $user->password = bcrypt($request->password);
        $user->save();

        return response()->json(['registered' => true ]);
    }

I'll appreciate of all your Help.
Thanks.