Safari Autofill not working on MacBook Air M3

Odd one here.

I currently own an old MBP 2018 and it's faultless, safari autofills all my details on all web pages. Same for my iPhone 16 Pro, autofill pulls all data from my card and populates in Safari.

Now to my 2024 M3 MBA, in Safari, the autofill icon turns blue, but doesn't populate any information. I can right click and go to autofill and it will pull some info (but will populate full name into "first name" box etc, doesn't splice the data).

Of course, autofill is selected for all categories in Safari settings.

Super frustrating and only thing letting down this great computer.

Any ideas?

Cheers.

[Re-Titled by Moderator]