When you change your password in LinkedIn, an orange warning sign (like on the picture below) will appear at the top part of your screen next to your account name.
When you click on this sign, you will see the page on the picture below. There, another orange sign appears next to the LinkedIn account with the problem.
If you hover over it, you will see the exact problem there is with your account. Clicking on it will lead you to another page in Expandi where you can solve it - in this case, where you can update the password.