When I sync to Shopify stock availability for items automatically get checked

Dear all
I have connected ERPNext with Shopify through private app,
when I register items in ERPNext I un-check their stock availability but after sync to Shopify stock availability of all items automatically get checked in ERPNext.
I don’t know where is the problem

ERPnex v10.1.17
please help me if anyone knows the issue
thanks

Before sync when I register

After sync