The bug has existed for years...
Usually it happen when application isn't completely loaded - calling function from initialise(), onStart() etc.
Maybe only during the first run after installing.or updating.
code only in text, forum restriction:
using Toybox.Application.Properties as PRP;
function getValue(value, property_key)//property_key is string and exist
{
if(property_key != null)
{
value = PRP.getValue(property_key);//<<<< Error Name: Unexpected Type Error
...
}