Application service problem

[RenatoRolando]

The library works well for me on razor page to add items (I add items and I see them on chrome debugger application section).

But when I try to use on my Class to retrieve data, I receive error:
The JSON value could not be converted to System.String. Path: $ | LineNumber: 0 | BytePositionInLine: 3. On blazor.webassempbly.js:1

On Program.cs I added:

builder.Services.AddLocalStorageServices();

Here the code

    private readonly ILocalStorageService _localStorageService;

    public CustomAuthenticationStateProvider(ILocalStorageService localStorageService)
    {
        _localStorageService = localStorageService;
    }

     var token = _localStorageService.GetItem<string>("MyToken");

the token "MyTonken" exists on Chrome.

also the using directive doesn't works (are grey)

using Blazor.Serialization.Extensions;
using System.Text.Json;

What I'm making wrong ?

Thanks!

[RenatoRolando]

I found the solution!

Even if you save a data as if it's a number you have to retrieve with otherwise you vill receive an error.

Thanks