Who to force a type

Hello,
In a C# class i have this property

public Type? Value1;

public Type? Value1;

And on the same class have this methode

public void test()
{
  if (Value1 != null)
  {
    Type Value2 = Value1;
  }
}

public void test()
{
  if (Value1 != null)
  {
    Type Value2 = Value1;
  }
}

C# would not compile because Type1 could be null and not Value2

How to edit test for granted Value1 is of type Type1 ?
I have try

Value1.HasValue

Value1.HasValue

in the if but that do the same

Thanks at advence