@Lousie23547089g2al as @davescm wrote, the Photoshop 'color settings' defaults are for new documents created in Photoshop. (so when you open a new blank file i.e. using - 'File > New').
When opening an existing file the preferred behaviour for most users is to preserve the embedded profile. So, the file stays in its existing color space, no conversion is made.
It seems like the files you are opening have the sRGB icc profile embedded.
What to do?
It is possible, in Photoshop's 'color settings', under 'Color Management Policies' (see screenshot below),
to select "convert to 'Working RGB' - in your case, this would be Adobe RGB, it seems.
If you open a file with sRGB embedded, and, if you have "Profile Mismatches" checked, as I did above, you'll get a pop up (see below) that states that the embedded profile is sRGB with the default behaviour to convert to Adobe RGB
so, should you wish to convert your image file to Adobe RGB, then you'd just click OK here.
If you want that default behaviour without the "embedded profile mismatch" pop-up then you'd uncheck Ask When Opening" (see my first screenshot). I generally don't recommend that because I like users to know the provenance of files they are opening and to take control of any profile-to-profile conversions.
Is that what you want to do? Make all your files Adobe RGB?
BTW, there is little point in converting sRGB to Adobe RGB unless you have a good reason to do so - as you're effectively pouring 2/3 pint into a pint pot. Maybe you want Adobe RGB to pass onto others, thats fine then, thats a good reason to convert
I hope this helps
neil barstow colourmanagement - adobe forum volunteer,
colourmanagement consultant & co-author of 'getting colour right'
See my free articles on colourmanagement online
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