C# - Reflection to invoke static method freezes unity

Hello,

I have a class like this:

 namespace MyTest
 {
     public interface TestI
     {

          //....
     }

     public class Test : TestI
     {
        public static Test GetInstance()
        {
             if (instance == null)
             {
                 instance = new Test();
             }
             return instance;
     
        }
     
         // ....
     }
 }

I have built it into a dll called "Test.dll". Now I want to invoke this static method with reflection.

 private void Start()
 {
   
     Assembly assembly = Assembly.LoadFrom("Test.dll");
     Type type = assembly.GetType("MyTest.Test");
     MethodInfo mi = type.GetMethod("GetInstance");
     MyTest.TestI test= (MyTest.TestI)mi.Invoke(null, null);
 }

None of calls in Start() return null, it appears to go through, but whenever I try to call a method Unity just freezes. What am I doing wrong?

EDIT: running on PC, but will eventually run on android/ios too. I get no exceptions.