Json TypeInfoResolver GetCustomAttribute returning wrong result

public void ModifyTypeInfo(JsonTypeInfo ti)
{
    if (ti.Kind != JsonTypeInfoKind.Object) return;
    
    
    for (var i = 0; i < ti.Properties.Count; i++)
    {
        var property = ti.Properties[i];
        if (
            property.PropertyType.GetCustomAttribute<IpcExposeAttribute>() is null // problem is here
        )
        {
            ti.Properties.RemoveAt(i--);
        }
    }
}

[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Property)]
public class IpcExposeAttribute : Attribute
{
    public string? InstanceName { get; }

    public IpcExposeAttribute(string instanceName)
    {
        InstanceName = instanceName;
    }

    public IpcExposeAttribute()
    {
        InstanceName = null;
    }
}

class Item(int id, string name)
{
    [IpcExpose] public int Id2 { get; set; } = id;
    
    public string Name2 { get; set; } = name;
}