Add family members ST app

I ran into the same problem today trying to add my wife as a user. When I tried to use the SmartThings classic app on her android phone, it would say she’s already logged in on the phone with her Samsung account and to continue or go into system settings and logout. I also noticed that after this happened, her e-mail address disappeared from the invited users in the SmartThings classic app on my android phone.

I then decided to login to her e-mail account on my laptop and accepted the invitation there. I was then able to login using her Samsung account. After that, the invited next to her e-mail address in my SmartThings app went away but her address stayed. I was then able to successfully open the SmartThings classic app on her phone and see all my devices.

@Highbar’s answer led to my success, but I have an iPhone and the 3-line menu is on the bottom-right.
After pressing that i see there is a V-shaped drop-down next to the gear-button on the top-right.
When I press the V-shaped drop-down, I see the shared location. After pressing that, I now can see and manage my device.

Thanks all for the comments/help.

Read Highbar’s note: make sure you have the correct “Home” chosen when you click the 3 lines. If you are on the second phone there probably is the original “Home” when you logged in (or with previous versions of the app) and the shared “Home” is listed below it, but hidden unless you click on the little arrow down.