ASP.NET Core - Let's Encrypt - No credentials are available in the security package while creating certificate

I'm trying to get Let's Encrypt certificate through ACME protocol for my web application by using Lettuce Encrypt. I'm facing an issue (underlined in red bellow) while starting my application, and requesting a new certificate :

Win32Exception (0x8009030E): No credentials are available in the security package

No credentials are available in the security package

My application is running as a Windows service (not with IIS). I configured Lettuce Encrypt this way in my Startup.cs file :

services.AddLettuceEncrypt().PersistDataToDirectory(new DirectoryInfo(certDirectory), "MyPfxPassword");

I'm trying to figure out where is my mistake. Could someone please help me about this topic ?