Adding Overclockers link doesn't trigger notification

Try to add an item which is in stock ex: https://www.overclockers.co.uk/corsair-vengeance-rgb-pro-black-32gb-2x16gb-3600mhz-amd-ryzen-tuned-ddr4-memory-dual-kit-my-4ck-cs.html

You won't receive notification, and it shows as not in stock