I maintain some Google accounts for an organization, as well as my personal account. When I want to bring up Drive or Photos for one of these organization accounts I click on my profile photo and select "add another account".
LastPass automatically populates the email field with the first Google account it finds.
I go into LastPass and select the account I want to login to (I have 15), which then correctly populates the email field. I click Next and LastPass populates the Password field.
However, the password it uses is the one for the first Google account, not the one I selected. This is consistent whichever account I choose.
The correct password is stored in the right place in LastPass.
I should add that this happens on a Windows 11 laptop under Chrome and Firefox.