Checkout Signin Scrolls To Top Of Page

Multi-Vendor Questions
1

Hi there

I'm new to CSCART, and i've stumbled across an issue after doing all upgrades up too 

 4.10.3.SP1

When on the checkout page before logging in and you try sign in as a returning customer it seems that instead of logging in, the page scrolls to the top.

However if i click on the sign in button under the my account menu item the popup works as expected.

So seems to be isolated to the form on the checkout page

I've incuded a link to an image of the form.

https://ibb.co/BBSbM70

Any ideas please?