Subtracted vector value from UV chord (Y) does not reflect in preview

[ripe pecan]

Hi community, I am doing exactly the same steps as this tutorial: https://www.youtube.com/watch?v=e8IFoLMdrl0 but can't seem to get the same outcome.
See timestamp 8:27 onwards when he adjusted the "subtract" node B value, it reduced the texture's coverage but for some reason mine does not do that despite connecting the same node.

See images of my actual outcome vs expected outcome showing how I connected in the material editor:
https://www.canva.com/design/DAGUpp7zWVc/91ZSTcSGYTakMVU74DrkLQ/view?utm_content=DAGUpp7zWVc&utm_campaign=designshare&utm_medium=link&utm_source=editor

Thanks in advance!

[lament hedge]

expand texture properties in material properties, set clamp mode(s) to Clamp to Border Color and adjust color to desired one..