why in the world an object has stopped being a referance type

all was writen right, and working just fine, than i checked again before sending assigment and it stopped behaving like referance type.

 

Are you expecting some help with the limited info you posted or are you just making some sort of statement?

 

https://imgur.com/a/Fwk7KY5

so... there is an empty object
there is sum to sum up numbers, i use it because its referance type.
than there is the method, it all worked fine.
now it stoped being referance type.
dont get it why, it all worked fine.

as you see it shows 40, than 0, than 15, than 40 again.
while it should be, 40, stay 40, 55, stay 55.

 

Resolved Thanks.